关于英语选择提

题目

关于英语选择提
--Is Pro.Smith giving the speech today
--It____be him .He is abroad right now.
A mustn't B needn't C won't D can't
请问选哪个 并为什么要选它呢?

答案

D
mustn't是禁止的意思
needn't 是不必要的意思
won't是将不会的意思
－Smith教授今天会做演讲吗?
－不可能是他.他现在在外国呢