They waited for seemed to be a long time hoping that rescue would come.A. itB. whichC. w

问题补充：

They waited for seemed to be a long time, hoping that rescue would come.

A. it

B. which

C. what

D. that

答案：

A. it

B. which

(答案→)C. what

D. that

解析：句意：看起来他们等了很长时间，希望救援可以到来。这个句子包含一个宾语从句，且引导词在从句中作主语，表示“什么”的意思，故用what，选C。