— Mary had an accident on her way to home yesterday— ? She is always careful．A. How comeB

问题补充：

— Mary had an accident on her way to home yesterday．

— ? She is always careful．

A. How come

B. Why not

C. So what

D. What for

答案：

(答案→)A. How come

B. Why not

C. So what

D. What for

解析：

试题分析:句意：——昨天玛丽在回家的路上出了点意外。——怎么会这样呢？她一向是很小心的。A怎么会这样呢？B为什么不呢？C那又怎样？D为了什么呢？从She is always careful．可以判断说话人对她出意外的事情表示惊讶，故答案选A。