Japan’s nuclear crisis (核危机) will be solved in is not known yet.A. ThatB. IfC. Wheth

问题补充：

Japan’s nuclear crisis (核危机) will be solved in is not known yet.

A. That

B. If

C. Whether

D. What

答案：

A. That

B. If

(答案→)C. Whether

D. What

解析：考查主语从句。 Japan’s nuclear crisis (核危机) will be solved in 在主从复合句 Japan’s nuclear crisis (核危机) will be solved in is not known yet中作主语。根据is not known yet，还不知道，可知主语从句表不确定，应由Whether引导，If不能引导主从。所以选C。