---Willyoupleaseanswerthedoor?. It

问题详情：

--- Will you please answer the door?.  It __________ be your sister.

Sorry, I ________ .I'm feeding the rabbit.

  A．must；mustn’t    B．will；can’t   C．may；can’t D．must；needn’t

【回答】

C

知识点：情态动词

题型：选择题