.................gold is perhaps .............. most highly treasured metal. A. the / X B. X / the C. the / the D. X / X

Genetic engineering is helping researchers unravel the mysteries of previously incurable diseases so that they can get to its root causes and find cures

Don't leave here, _    ?

Without any hesitation, he did a decision not to take the course

One of the four underlined parts marked A, B, C, D in each sentence is not correct in standard English. Identify them: 

What you would do if you could speak French well? 

Nuclear energy, despite its early promise as a source of electrical power, is still insignificant in compared with older and safer energy sources.

After writing it , the essay must be duplicated by the the student himself and handed into the department secretary before the end of the month.

The geology professor showed us a sample about volcanic rock which dated back seven hundred years.

The evolution of fishes is a history of constant adaptation to new possibilities, and a refined of these adaptations.

He seldom goes to the park, _    ?

A fragrant plant has tiny sacs that makes and stores the substances that give it a pleasant odor.

Choose the correct answer to complete the sentence. "Most people admit that they _____ to global warming"

Once the scientist had figured out the precise path of the comet, he is finding that he was able to predict its next appearance.

Because of it consists only of a relatively short strand of DNA protected by a shell of Protein, a virus cannot eat or reproduce by it self.

Deep cratered, the moon is over 2100 miles in diameter with negligible gravity and atmosphere.

The young are thought to be the future leaders of the country, and it is essential that they should understand their heritage as full as possible.

Philosophy, the inquiry into the nature of  human knowledge, it is still a very popular subject among university students

Mosquitoes will accepts the malaria parasite at only one stage of the parasite’s complex life cycle.

In spite of her physician handicaps, Helen Keller graduated from Radcliffe with honors

The Department of Foreign Languages are not located in the new building opposite the old one.

Deciduous trees are ones that lose its leaves in the autumn and grow new ones in the spring.