Each sentence has a mistake. Find it bychosing A B C or D

Review sometimes describe books  as ‘hard-to-put-down’, or ‘hard-to-pick-up-again’

Read the following passage and choose the best answer (A, B, C, D):
In Africa, people celebrate with joy the birth of a new baby. The Pygmies would sing a birth-song to the child. In Kenya, the mother takes the baby strapped to her back into the thorn enclosure where the cattle is kept. There, her husband and the village elders wait to give the child his or her name. In West Africa, after the baby is eight days old, the mother takes the baby for it’s first walk in the big, wide world, and friends and family are invited to meet the new baby. In various African nations, they hold initiation ceremonies for groups of children instead of birthdays. When children reach a certain designated age, they learn the laws, beliefs, customs, songs and dances of their tribes. Some African tribes consider that children from nine to twelve are ready to be initiated into the grown up world. They may have to carry out several tests. Masai boys around thirteen years old to seventeen undergo a two stage initiation. The first stage lasts about three months. The boys leave their parents’ homes, paint their bodies white, and are taught how to become young warriors. At the end of this stage, they have their heads shaved and they are also circumcised. The second stage, the young warriors grow their hair long and live in a camp called a manyatta where they practice hunting the wild animals that might attack the Masai herds. This stage may last a few years. When they are ready, they will marry and become owners of large cattle herds like their fathers. The girls are initiated when they are fourteen or fifteen. They are taught by the older women about the duties of marriage and how to care for babies. Soon after that they are married and lead a life similar to that of their mothers  
5. The word “shaved” in paragraph 3 mostly means __________

Choose the best answer:
When/ we/ go/ back/ the bookstore, we/ buy/ book/ we/ wanted.

Read the following passage and choose the best answer (A, B, C, D):
All relationships go through difficult times. In the past, when married couples had problems they usually didn’t (1) _____. They had to either get on well with each other or continue to live together in an unhappy relationship. Getting divorced wasn’t an (2)_____ for most people due to economic and social reasons. Some people believe that this wasn’t such a bad thing. They say that relationships require hard work and (3) ______. “If a relationship is going to last a lifetime, you have to keep working at it,” says Doreen, who is celebrating her fiftieth wedding anniversary this year. “It isn’t all roses and romance. No one perfect all of the time. These days young people give up (4)_______ there’s the slightest argument.” Experts agree that communication is key. The most important thing is to keep talking. How many times have you heard yourself say to somebody, “If only you’d listen!” or “I wish you wouldn’t do that!” The truth is, the (5) ______ couples talk, the better their relationship can be

Read the following passage and choose the best answer (A, B, C, D):
Dr. Daniel Quon has been an oral surgeon in Jackson for over 30 years. “Growing up  in the family business, I knew that in order for you to gain something, you have to give back,” Quon said. “And being in the field of dentistry, we have a special gift that we can help people and I thought that was an appropriate way to help out.”  Quon volunteers his dental services at the Jackson Free Health Clinic to patients who can’t afford it. Through the Mississippi Dental Association, Quon also provides free dental care for the Mission Service of Mercy program. Dental Assistant Carley Welch has been a part of this experience. “We actually did that last year together and we plan on doing that again this year together,” he said. “Best boss you can ask for,” Welch continued. “Very patient, always willing to teach you; even things that most people wouldn’t go very far to teach you, he will. Just so you have the experience.” But Quon serves in other ways too. “Wife and I volunteer at the Stewpot. We serve lunch on Saturdays when we can. I was actually on the board of Stewpot for 3 years until this passed year.” And he donates blood platelet at the Mississippi Blood services. “I’m almost up to 18 gallons right now in donations. That’s a lot of blood! still got a little bit left though.” “It takes very little time to volunteer. It’s a great thing where you can help someone who needs an extra hand or helping hand.” “I think he does his part to contribute as much as possible,” Welch added. “Whether it’s helping dental wise or even just in general with the public.” 
1. Which best serves as the title for the passage?

Choose the best answer:
Most tourist attractions in London charge an admission __________.

Read the following passage and choose the best answer (A, B, C, D):
Naturalists in the developed countries were largely split between conservationists and  preservationists. This battle is no better demonstrated in the US than during the Progressive Era of 1890-1920.  While the existing economic paradigm was one of laissez-faire economics that many felt was damaging the natural environment and integrity of natural resources, the conservationist movement led by Theodore Roosevelt was deeply concerned about the wastage and harm it was doing to the land, leading to a large number of game species in the US on the brink of extinction in less than a century. Then there were the preservationists who argued that the proposals of the emerging conservationists did not go far enough. This was certainly the view of John Muir who believed that there was still too much concern for the economic value of land rather than the need for preservation of pristine landscapes. Muir’s Sierra Club made a stand with the development of the Hetch Hetchy Dam in Yosemite, arguing that the land should be kept pristine and the valley protected.  As president, Roosevelt pushed strongly for conservation issues which may be the reason they eventually won the day. During his term in office, around 230m acres of land were put under Federal protection, established the US Forestry Service, and created five national parks, and several national forests. That’s not to say that preservationists did not have their victories. In the 1960s, the Wilderness Actset aside large tracts of land with minimal human impact and of particular cultural, scientific, or natural interest. In these areas, logging, mining and other industrial activities are prohibited and there are strong protections in place to maintain the integrity of natural water sources partly for the ecosystem and partly for industrial and commercial developments downstream of the water flow. 
2. The word “split” in paragraph 1 can be replaced by ______

Read the following passage and choose the best answer (A, B, C, D):
Political and economic reforms launched in 1986 have transformed the country from  one of the poorest in the world, with per capita income around US $100, to lower middle income status within a quarter of a century with per capita income of around US$ 2,100 by the end of 2015.  Vietnam’s per capita GDP growth since 1990 has been among the fastest in the world, averaging 5.5 percent a year since 1990, and 6.4 percent per year in the 2000s. Vietnam’s economy continued to strengthen in 2015, with estimated GDP growth rate of 6.7 percent for the whole year.  The Vietnamese population is also better educated and has a higher life expectancy than most countries with a similar per capita income. The maternal mortality ratio has dropped below the upper-middle-income country average, while under-five mortality rate has fallen by half, to a rate slightly above that average. Access to basic infrastructure has also  improved substantially. Electricity is now available to almost all households, up from less than half in 1993. Access to clean water and modern sanitation has risen from less than 50 percent of all households to more than 75 percent.  Vietnam’s Socio-Economic Development Strategy (SEDS) 2011-2020 gives attention to structural reforms, environmental sustainability, social equity, and emerging issues of macroeconomic stability. It defines three “breakthrough areas”: promoting human resources/skills development (particularly skills for modern industry and innovation), improving market institutions, and infrastructure development. In addition, the five-year Socio-Economic Development Plan 2011-2015 focused on three critical restructuring areas - the, banking sector, state-owned enterprises and public investment that are needed to achieve these objectives. The recent draft of the SEDP 20162020 acknowledges the slow progress of the reform priorities of the SEDP 2011-2015. With agriculture still accounting for almost half the labor force, and with significantly lower labor productivity than in the industry and services sectors, future gains from structural transformation could be substantial. The transformation from state to private ownership of the economy is even less advanced. The state also wields too much influence in allocating land and capital, giving rise to heavy economy wide inefficiencies. So, adjusting the role of the state to support a competitive private sector-led market economy remains a major opportunity. This will be important for enhancing productivity growth which has been stagnating for a long time.
3. Which of the followings is NOT mentioned as an example of development in Vietnam?

Read the following passage and choose the best answer (A, B, C, D):
Political and economic reforms launched in 1986 have transformed the country from  one of the poorest in the world, with per capita income around US $100, to lower middle income status within a quarter of a century with per capita income of around US$ 2,100 by the end of 2015.  Vietnam’s per capita GDP growth since 1990 has been among the fastest in the world, averaging 5.5 percent a year since 1990, and 6.4 percent per year in the 2000s. Vietnam’s economy continued to strengthen in 2015, with estimated GDP growth rate of 6.7 percent for the whole year.  The Vietnamese population is also better educated and has a higher life expectancy than most countries with a similar per capita income. The maternal mortality ratio has dropped below the upper-middle-income country average, while under-five mortality rate has fallen by half, to a rate slightly above that average. Access to basic infrastructure has also  improved substantially. Electricity is now available to almost all households, up from less than half in 1993. Access to clean water and modern sanitation has risen from less than 50 percent of all households to more than 75 percent.  Vietnam’s Socio-Economic Development Strategy (SEDS) 2011-2020 gives attention to structural reforms, environmental sustainability, social equity, and emerging issues of macroeconomic stability. It defines three “breakthrough areas”: promoting human resources/skills development (particularly skills for modern industry and innovation), improving market institutions, and infrastructure development. In addition, the five-year Socio-Economic Development Plan 2011-2015 focused on three critical restructuring areas - the, banking sector, state-owned enterprises and public investment that are needed to achieve these objectives. The recent draft of the SEDP 20162020 acknowledges the slow progress of the reform priorities of the SEDP 2011-2015. With agriculture still accounting for almost half the labor force, and with significantly lower labor productivity than in the industry and services sectors, future gains from structural transformation could be substantial. The transformation from state to private ownership of the economy is even less advanced. The state also wields too much influence in allocating land and capital, giving rise to heavy economy wide inefficiencies. So, adjusting the role of the state to support a competitive private sector-led market economy remains a major opportunity. This will be important for enhancing productivity growth which has been stagnating for a long time.
7. What does the word "stagnating" in the last paragraph mean?

Read the following passage and choose the best answer (A, B, C, D):
Elephants need a large amount of habitat because they eat so much. Humans have become their direct competitors for living space. Human populations in Africa and Asia have quadrupled since the turn of the century, the fastest growth rate on the planet. Forest and savanna habitat has been converted to cropland, pastureland for livestock, and timber for housing and fuel. Humans do not regard elephants as good neighbors. When humans and elephants live close together, elephants raid crops, and rogue elephants rampage through villages. Local people shoot elephants because they fear them and regard them as pests. Some countries have established culling programs: park officials or hunters kill a predetermined number of elephants to keep herds manageable and minimize human-elephant conflicts. Hunting has been a major cause of the decline in elephant populations. Elephants became prized trophies for big-game hunters after Europeans arrived in Africa. More recently, and more devastatingly, hunters have slaughtered elephants for their ivory tusks. The ivory trade became a serious threat to elephants in the 1970s. A sudden oil shortage caused the world economy to collapse, and ivory became more valuable than gold. In fact, ivory has been called “white gold” because it is beautiful, easily carved, durable, and pleasing to the touch. Most of the world’s ivory is carved in Japan, Hong Kong, and other Asian countries, where skilled carvers depend on a supply of ivory for their livelihoods  Hunting elephants is no longer legal in many African countries, but poaching was widespread until very recently. For many the high price of ivory, about $100 a pound in the 1980s, was too tempting to resist. Local people often had few other ways to make a living, and subsistence farmers or herders could make more by selling the tusks of one elephant than they could make in a dozen years of farming or herding. As the price of ivory soared, poachers became more organized, using automatic weapons, motorized vehicles, and airplanes to chase and kill thousands of elephants. To governments and revolutionaries mired in civil wars and strapped for cash, poaching ivory became a way to pay for more firearms and supplies. Poaching has caused the collapse of elephants’ social structure as well as decimating their numbers. Poachers target the biggest elephants because their tusks are larger. They often kill all the adults in the group, leaving young elephants without any adults to teach them migration routes, dry-season water sources, and other learned behavior. Many of Africa’s remaining elephant groups are leaderless subadults and juveniles.
1. What is the main idea of the passage?

Choose the best answer:
.............. he drank, ................ he became.

Read the following passage and choose the best answer (A, B, C, D):
Thunderstorms, with their jagged bursts of lightning and roaring thunder, are actually one of nature’s primary mechanisms for transferring heat from the surface of the earth into the atmosphere. A thunderstorm starts when low-lying pockets of warm air from the surface of the earth begin to rise. The pockets of warm air float upward through the air above that is both cooler and heavier. The rising pockets cool as their pressure decreases, and their latent heat is released above the condensation line through the formation of cumulus clouds. What will happen with these clouds depends on the temperature of the atmosphere. In winter, the air temperature differential between higher and lower altitudes is not extremely great, and the temperature of the rising air mass drops more slowly. During these colder months, the atmosphere, therefore, tends to remain rather stable. In summer, however, when there is a high accumulation of heat near the earth’s surface, in direct contrast to the considerably colder air higher up, the temperature differential between higher and lower altitudes is much more pronounced. As warm air rises in this type of environment, the temperature drops much more rapidly than it does in winter; when the temperature drops more than 4 degrees Fahrenheit per thousand feet of altitude, cumulus clouds aggregate into a single massive cumulonimbus cloud, or thunderhead. In isolation, a single thunderstorm is an impressive but fairly benign way for Mother Earth to defuse trapped heat from her surface; thunderstorms, however, can appear in concert, and the resulting show, while extremely impressive, can also prove extraordinarily destructive. When there is a large-scale collision between cold air and warm air masses during the summer months, a squall line, or series of thunderheads, may develop. It is common for a squall line to begin when an advancing cold front meets up with and forces itself under a layer of warm and moist air, creating a line of thunderstorms that races forward at speeds of approximately forty miles per hour. A squall line, which can be hundreds of miles long and can contain fifty distinct thunderheads, is a magnificent force of nature with incredible potential for destruction. Within the squall line, often near its southern end, can be found supercells, long-lived rotating storms of exceptional strength that serve as the source of tornadoes.
7. All of the following are mentioned in the passage about supercells EXCEPT that they ________

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions:
In the United States, presidential elections are held in years evenly divisible by four (1888, 1900, 1964, etc.). Since 1840, American presidents elected in years ending with zero have died in office, with one exception. William H. Harrison, the man who served the shortest term, died of pneumonia only several weeks after his inauguration.
Abraham Lincoln was one of four presidents who were assassinated. He was elected in 1860, and his untimely death came just five years later. James Garfield, a former Union army general from Ohio, was shot during his first year in office (1881) by a man to whom he wouldn’t give a job. While in his second term of office (1901), William McKinley, another Ohioan, attended the Pan-American Exposition in Buffalo, New York. During the reception, he was assassinated while shaking hands with some of the guests. John F. Kennedy was assassinated in 1963 in Dallas only three years after his election.
Three years after his election in 1920, Warren G, Harding died in office. Although it was never proved, many believe he was poisoned. Franklin Roosevelt was elected four times (1932, 1936, 1940 and 1944), the only man to serve so long a term. He had contracted polio in 1921 and eventually died of the illness in 1945.
Ronald Reagan, who was elected in 1980 and reelected four years later, suffered an assassination attempt but did not succumb to the assassin’s bullets. He was the first to break the long chain of unfortunate events. Will the candidate in the election of 2020 also be as lucky?

The word “assassinated” in the second paragraph is closest in meaning to     .

Read the following passage and choose the best answer (A, B, C, D):
The first two decades of this century were dominated by the microbe hunters. These hunters had tracked down one after another of the microbes responsible for the most dreaded scourges of many centuries: tuberculosis, cholera, diphtheria. But there remained some terrible diseases for which no microbe could be incriminated: scurvy, pellagra, rickets, beriberi. Then it was discovered that these diseases were caused by the lack of vitamins, a trace substance in the diet. The diseases could be prevented or cured by consuming foods that contained the vitamins. And so in the decades of the 1920’s and 1930’s, nutrition became a science and the vitamin hunters replaced the microbe hunters. In the 1940’s and 1950’s, biochemists strived to learn why each of the vitamins was essential for health. They discovered that key enzymes in metabolism depend on one or another of the vitamins as coenzymes to perform the chemistry that provides cells with energy for growth and function. Now, these enzyme hunters occupied center stage. You are aware that the enzyme hunters have been replaced by a new breed of hunters who are tracking genes – the blueprints for each of the enzymes – and are discovering the defective genes that cause inherited diseases – diabetes, cystic fibrosis. These gene hunters, or genetic engineers, use recombinant DNA technology to identify and clone genes and introduce them into bacterial cells and plants to create factories for the massive production of hormones and vaccines for medicine and for better crops for agriculture. Biotechnology has become a multibilliondollar industry. In view of the inexorable progress in science, we can expect that the gene hunters will be replaced in the spotlight. When and by whom? Which kind of hunter will dominate the scene in the last decade of our waning century and in the early decades of the next? I wonder whether the hunters who will occupy the spotlight will be neurobiologists who apply the techniques of the enzyme and gene hunters to the funtions of the brain. What to call them? The head hunters. I will return to them later.
7. The author implies that the most important medical research topic of the future will be: 

Read the following passage and choose the best answer (A, B, C, D):
Super Size Me is a 2004 film by Morgan Spurlock, in which he (1)____ his experiment to eat only McDonald’s fast food three times a day, every day, for thirty days. Spurlock made himself a short list of rules for the experiment, including an obligation to eat all of the three meals he ordered. He also had to ‘Super Size’, which means (2) ______ a giant portion every time the option was offered to him. He ended up vomiting after the first Super Size meal he finished, after taking nearly twenty minutes to consume it. After five days Spurlock put on almost 5kg, and he soon found himself feeling depressed, with no energy. The only thing that got rid of his headaches and made him feel better was another McDonald’s meal, so his doctors told him he was addicted. More seriously, around day twenty, he started experiencing heart (3)________ and one of the doctors detected liver problems. However, in spite of his doctor’s advice, Spurlock continued to the end of the month and achieved a total weight gain of 11kg. His body mass index also increased from a healthy 23.2 to an overweight 27. It took Spurlock fifteen months to recover (4)_______ his experiment and return to his original weight, but the film also had a wider impact. Just after its showing in 2004, McDonald’s phased out the Super Size option and healthier options like salads appeared on the menu. Unfortunately, McDonald’s denied the connection between the film and the changes, but it is interesting to note how closely they (5)________ with the release of the film

Each sentence has a mistake. Find it bychosing A B C or D

 Starches provide important nutrients and satisfy hunger without  add excess weight

Read the following passage and choose the best answer (A, B, C, D):
Individual differences in temperament or behavioral styles are important in family life  in several ways because they affect the nature of the interactions among family members. Some children adapt quickly and easily to family daily routines and get along well with their siblings. Others, especially highly active, intense and “prickly” children have a more difficult time adjusting to everyday demands, and their interactions with parents and siblings may lead to friction and stress. Consider how an active, impulsive child can bother an older sibling who is trying to complete a school project, or how a distractible child who is low in persistence can frustrate parents’ efforts to get him to complete his homework or to finish a household chore.  It is important to note that parents, like children, also differ in temperament. Some are quick reacting and intense, while others are quiet and slow to respond; some are flexible and adaptable, and others are not. The “mix” between parents’ and children’s temperaments has a strong effect on family life, sometimes leading to positive interactions, sometimes to frustrations, and sometimes even to conflicts. It is interesting to note that parents also differ in the expectations they have about their children’s behavior, and how they view and tolerate differences in temperaments. For example, certain constellations of temperament such as high activity, intensity, and persistence may be tolerated and valued in boys, but not in girls. Conversely, shyness and sensitivity may be viewed as acceptable in girls, but not in boys.  This leads to the notion of “goodness of fit”, which can be a useful framework for helping parents figure out how temperament affects relationships in the family. “Goodness of fit” refers to the match or mismatch between a child and other family members. For example, a high-activity, intense child may upset and irritate a quiet, slow-paced, reflective parent. An active, quick-responding parent may be impatient with a slow-to-warm-up child, whom the parent may see as lazy or indifferent. Sparks may fly when both parent and child are intense and quick responding.  Life in a family is not the same for all children, and temperament is one of the ingredients in the “fit” between child and family. Don’t assume family friction is a result of your child having LD or ADHD. It could be because of your child’s temperament — and yours! 
1. Which best serves as the title for the passage?

Read the following passage and choose the best answer (A, B, C, D):
Without regular supplies of some hormones our capacity to behave would be seriously impaired; without others we would soon die. Tiny amounts of some hormones can modify our moods and our action, our inclination to eat or drink, our aggressiveness or submissiveness, and our reproductive and parental behavior. And hormones do more than influence adult behavior; early in life they help to determine the development of bodily form and may even determine an individual’s behavioral capacities. Later in life the changing outputs of some endocrine glands and the body’s changing sensitivity to some hormones are essential aspects of the phenomena of aging. Communication within the body and the consequent integration of behavior were considered the exclusive province of the nervous system up to the beginning of the present century. The emergence of endocrinology as a separate discipline can probably be traced to the experiments of Bayliss and Starling on the hormone secretion. This substance is secreted from cells in the intestinal walls when food enters the stomach; it travels through the bloodstream and stimulates the pancreas to liberate pancreatic juice, which aids in digestion. By showing that special cells secrete chemical agents that are conveyed by the bloodstream and regulate distant target organs or tissues, Bayliss and Starling demonstrated that chemical integration can occur without participation of the nervous system. William Bayliss and Ernest Henry Starling, two British physiologists, discovered and introduced the word hormone. In 1979, The Bayliss and Starling Society was founded as a forum for research scientists with specific interest in the chemistry, physiology and function of central and autonomic peptides. The Society also offered the travelling fellowship award for members who wanted to attend national and international academic conferences. Sometimes, the Society help schools to organize science fairs for secondary students and give them incentives to fall for related subjects. The term “hormone” was first used with reference to secretion. Starling derived the term from the Greek hormone, meaning “to excited or set in motion.” The term “endocrine” was introduced shortly thereafter, “Endocrine” is used to refer to glands that secrete products into the bloodstream. The term “endocrine” contrasts with “exocrine” which is applied to glands that secrete their products through ducts to the site of action. Examples of exocrine glands are the tear glands, the sweat glands, and the pancreas, which secretes pancreatic juice through a duct into intestine. Exocrine glands are also called duct glands, while endocrine glands are called ductless.
4. It can be inferred from the passage that, before the Bayliss and Starling experiments, most people believed that chemical integration occurred only ________ .

Read the following passage and choose the best answer (A, B, C, D):
For nearly all of human history, there haven’t been that many of us. Around the year zero, Earth’s population is estimated to have been 190 million. A thousand years later, it was probably around 250 million. Then the Industrial Revolution happened, and human population went into overdrive. It took hundreds of thousands of years for humans to hit the 1 billion mark, in 1800. We added the next billion by 1928. In 1960, we hit 3 billion. In 1975, 4 billion. That sounds like the route to an overpopulation apocalypse, right? To many midcentury demographers, futurists, and science fiction writers, it certainly predicted one. Extending the timeline, they saw a nightmarish future ahead for humanity: human civilizations constantly on the brink of starvation, desperately crowded under horrendous conditions, draconian population control laws imposed worldwide. Stanford biologist Paul Ehrlich wrote in his best-selling book, “In the 1970’s, hundreds of millions of people will starve to death” because of overpopulation. None of that ever came to pass. The world we live in now, despite approaching a population of nearly 8 billion, looks almost nothing like the one doomsayers were anticipating. Starting in the 19th century in Britain and reaching most of the world by the end of the 20th century, birthrates plummeted — mostly because of women’s education and access to contraception, not draconian population laws. In wealthy societies where women have opportunities outside the home, the average family size is small; in fact, it’s below replacement level. Called the demographic transition, it is one of the most important phenomena for understanding trends in global development.  There’s still significant debate among population researchers about the extent of the sea change in population trends. Researchers disagree on whether global populations are currently on track to start declining by midcentury. There’s also disagreement on what the ideal global population figure would be, or whether it’s morally acceptable to aim for such a figure. While academic research seeks to nail down these questions, it’s important to be clear what is consensus among researchers. Our projections around population are used to make global health and development policy. They’re critical for planning, especially about climate change. Fears of overpopulation sometimes turn into hostility to immigrants, those who choose to have large families, and countries in an earlier stage of their population transition. Having an informed conversation about population is crucial if we are to get humanity’s future right.  
1. What is the main topic of the passage?

Read the following passage and choose the best answer (A, B, C, D):
With 13,000 floral species and over 15,000 faunal species, three newly discovered big animal species, and a ratio of country/world species of 6.3%. Vietnam has enormous tourismparticularly ecotourism-potential. In fact, since 1986, when Renovation Reforms began the shift from a centrally planned to a socialist-oriented market, or multi-sectoral, economy, tourism has been an sector of primary concern to the government. In May 1995, the prime minister of Vietnam approved a master plan of tourism development for the period 1995- 2010. In February 1999, the state decree on tourism was part of the socio-economic development strategy for the period 2001-2010 approved at the IX National Congress of the Party: “Tourism development has become a spearhead economic industry indeed. It is necessary to improve the quality and effectiveness of tourism activities, bringing into full play the natural conditions, and cultural and historical tradition to meet the domestic and international demand for tourism and to catch up with tourism development in the region” (Document of the IX National Congress 2001). Tourism has so far brought great benefits to the economy, but it has also contributed to environmental degradation, especially biodiversity deterioration. Thus, the concept of “sustainable development”-development which meets the needs of the present without compromising the ability of future generations to meet their own needs - must be factored into tourism development. This consideration is reflected in the term “ecotourism,” which is referred to variously as ecological or environmental tourism, nature or green tourism, sustainable or responsible tourism. Ecotourism involves travel to relatively undisturbed natural areas with the specific object of studying, admiring, and enjoying scenery, plants, and animals, as well as any cultural features found in these areas. It is distinguished from mass or resort tourism by its lower impact on the environment, lower infrastructure requirements, and its role in educating tourists about natural environments and cultural values. Fully aware of its significance, the government of Vietnam has prioritized ecotourism in its strategy for tourism development to ensure both sustainability and economic benefits. Though ecotourism in Vietnam is at a beginning stage of development, it is expected to grow strongly through support from government and international organizations.  
4 Which of the following is NOT mentioned as “ecotourism”?

Read the following passage and choose the best answer (A, B, C, D):
Just as optical fibers have transformed communication, they are also revolutionizing medicine. These ultra - thin, flxible fiers have opened a window into the living tissues of the body. By inserting optical fibers through natural openings or small incisions and the threading them along the body's established pathways, physicians can look into the lungs, intestines, heart and other areas that were formerly inaccessible to them. The basic fiber-optics system is called fiberscope, which consists of two bundles of fibers. One, the illuminating bundle, carries light to the tissues. It is coupled to a high-intensity light source. Light enters the cores of the high-purity silicon glass and travels along the fibers. A lens at the end of the bundle collects the light and focuses it into the other bundle, the imaging bundle. Each fibers in the bundle transmits only a tiny fraction of the total image. The reconstructed image can be viewed through an eyepiece or displayed on a television screen. During the last five years, improved methods of fabricating optical fibers have led to a reduction in fiberscope diameter and an increase in the number of fibers, which in turn has increased resolution. Optical fibers can also be used to deliver laser light. By use of laser beams, physicians can perform surgery inside the body, sometimes eliminating the need of invasive procedures in which healthy tissue must be cut through to reach the site of disease. Many of these procedures do not require anesthesia and can be performed in a physician's office. These techniques have reduced the risk and the cost of medical care.
4. The word "them" inparagraph 1, refers to: