Câu hỏi:

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 31 to 35.

Everyone wants to reduce pollution. But the pollution problem is (31)______ complicated as it is serious. It is complicated because much pollution is caused by things that benefit people.(32)______, exhaust from automobiles causes a large percentage of air pollution. But the automobile provides transportation for millions of people.

Factories discharge much (33)______ the material that pollutes the air and water, but factories give employment to a large number of people.

Thus, to end or greatly reduce pollution immediately, people would have to stop using many things that benefit them. Most of the people do not want to do that, of course. But pollution can be (34)______ reduced in several ways.

Scientists and engineers can work to find ways to lessen the amount of pollution that such things as automobiles and factories cause. Governments can pass and enforce laws that (35)______ businesses and traffic to stop, or to cut down on certain polluting activities.

Điền ô 34