問題詳情
【題組】53. The greenhouse effect____.
(A) did not have an influence on the earth until the Industrial Revolution
(B) does nothing but harm to humanity
(C) keeps the earth warm
(D) causes the carbon dioxide concentration in the atmosphere to increase
參考答案
答案：C
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)