Passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word for each of the blanks from 11 to 20

      Everyone wants to reduce pollution. But the pollution problem is (11) ________ complicated as it is serious . It is complited (12) ________ much pollution is caused by things that benefit people. (13) ________, exhaust from automobiles causes a lartge percentage of air pollution . But the automobile (14) ________ transportation for millions of people . Factories discharge much (15)_____ the material that pollutes theair and water, but factories give employment to a large munber of people . Thus , to end (16)________ greatly reduce pollution immediately , people would have to ( 17)________ using many things that benefit them . Most of the people do not want to do that , of course . But pollution can be (18)________ reduced in several ways . Scientists and engineers can work to find ways lessen the (19)________. Of the pollution that such things as automobiles and factories cause . Governments can pass and enforce laws that (20) ________ businesses and traffic to stop , or to cut down on certain polluting activities.

Điền vào số (17)

A. stop       

B. go on      

C. start        

D. continue