問題詳情

32. Doctors and scientists are beginning to conduct experiments on _______________ causedifferent kinds of health risks.
(A) air pollution can
(B) that air pollution
(C) how air pollution
(D) how air pollution can

參考答案

答案:D
難度:非常困難0
統計:A(0),B(0),C(0),D(0),E(0)

內容推薦