He failed in the exam proves that he wasn’t working hard enough.A. whichB. whatC. itD.

问题补充：

He failed in the exam, proves that he wasn’t working hard enough.

A. which

B. what

C. it

D. that

答案：

(答案→)A. which

B. what

C. it

D. that

解析：可联系答.案.网客服索取。