They asked me___ last night ,but I was unable to tell them.

问题描述:

They asked me___ last night ,but I was unable to tell them.
A.What was happened B.what happened
C.was what happened
D.what it happened
请说明原因

B
happen 不及物动词,没有被动语态,排除A与C; 而WHAT 作主语,不用IT ,再排除D
加油!不明白再问!