_____troublesmeis_____Idon’tknow_____istobedonewiththen...

问题详情：

_____ troubles me is _____ I don’t know _____ is to be done with the new machine.

A. What; what; that                         B. What; that; how 

C. What; that; what                         D. What; because; which

【回答】

知识点：复合句

题型：选择题