—Thelightisstilloninhisroom.Doyouknow         ?—Maybehe...

问题详情：

— The light is still on in his room. Do you know          ?

— Maybe he has to study for a test.

A. if he works hard                     B. who he is studying with

C. what he is busy with                  D. when he will stop working

【回答】

C

知识点：宾语从句

题型：选择题