China has offered much help to Japan since it by the earthquake and tsunami（海啸）.A. hitsB.

问题补充：

China has offered much help to Japan since it by the earthquake and tsunami（海啸）.

A. hits

B. is hit

C. was hit

D. will be hit

答案：

A. hits

B. is hit

(答案→)C. was hit

D. will be hit

解析：大地震冲击日本是过去发生的事，从句主语是it为动作的承受者，故要用过去时的被动句，结构为was（主语为it）+过去分词，故选C。