– There’s somebody at the door. Who it be? Is it the postman?-- No. It be him. It’s just

– There’s somebody at the door. Who it be? Is it the postman?
-- No. It be him. It’s just seven o’clock. It’s too early.
A. must, may not
B. will, won’t
C. may, mustn’t
D. may, can’t

A. must, may notB. will, won’tC. may, mustn’tD. may, can’t解析：may可以，可能；will会，将要；must必须，一定；can’t不能，不可能；won’t不会；mustn’t禁止，句意：有人在敲门。可能是谁？是邮递员吗？——不，不可能是他。现在刚七点。太早了。结合语境可知选D。

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