—Computer is so useful. It can do almost everything.
—Yes, but it what to do.
A. will tell
B. has known
C. must be told
D. is told
网友回答
A. will tell
B. has known
(答案→)C. must be told
D. is told
解析：根据语境可知此句的含义是电脑很有用,它几乎能做任何事情,但它必须被告诉做什么.因主语是it,是动词的承受者,故用被动语态,根据语气可知要用含有情态动词的故用C.