They___ the film at that time a.may see b.mustn't see c.must have_英语解答

They___ the film at that time a.may see b.mustn't see c.must have been d.can have seen
They___ the film at that time a.may see b.mustn't see c.must have been d.can have seen

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解答

C
must have done 一定已经,对发生过的事作以肯定推测