The time has come we can make extensive use of nuclear energyA. whenB. whichC. sinceD. w

问题补充：

The time has come we can make extensive use of nuclear energy．

A. when

B. which

C. since

D. while

答案：

(答案→)A. when

B. which

C. since

D. while

解析：考查定语从句，先行词是The time，且定语从句 we can make extensive use of nuclear energy缺少时间状语，所以用when引导。选A。