Mr Bush is on time for everything. How ________ it be that he was late for the opening ceremony?

Mr Bush is on time for everything. How ________ it be that he was late for the opening ceremony?

A.can

B.should

C.may

D.must

答案及解析： A

解析：

can表示可能性的推测，常用于疑问句或否定句中；

may表“可能性”常用于肯定句或否定句中；

must常用于肯定句中表推测，“一定……”的意思．