Do you think the reason he gave is believable?A. for whichB. whichC. whyD. what

问题补充：

Do you think the reason he gave is believable?

A. for which

B. which

C. why

D. what

答案：

A. for which

(答案→)B. which

C. why

D. what

解析：先行词the reason在定语从句he gave中用作宾语，故排除A，C，D三项。