ADMICRO

Read the passage below carefully and choose the correct answer a, b, c, or d.

Hundreds of thousands of persons each year fall prey to some type of cancer, but new methods of radiation therapy have enabled doctors to save more lives than ever before. Medical researchers have developed several experimental forms of this time-honored cancer treatment that seem effective in fighting the disease.

One promising approach involves exposing cancer cells to radiation by implanting a radioactive source directly into the malignant tissue. This process greatly increases the dosage and thus the effectiveness of the treatment. Another technique uses drugs to make cancer cells more susceptible to the effects of radiation and to make normal cells more resistant. Certain hugs are able to neutralize the genetic framework of cancer cells, thus making them easily affected by radiation. Both techniques have seen some positive results in the treatment of inoperable brain tumors.

These and other methods have helped to raise the recovery rate for cancer victims from 30 percent 40 years ago to around 50 percent today. This is encouraging news for those who fall prey to one of the world’s leading killers.

The word ‘malignant’ in paragraph 2 most closely means ________ .

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ZUNIA12
ZUNIA9
AANETWORK