問題詳情
41. Oil and natural gas exist on this planet in a limited supply.
Therefore, it is essential for us to develop _____ to these
nonrenewable energy sources.
(A) alternatives
(B) explosives
(C) infinitives
(D) relatives
參考答案
答案：A
統計：A:22,B:4,C:4,D:3,E:0
難度：簡單