Question

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

1. A.
   can
2. B.
   should
3. C.
   may
4. D.
   must

Answer 1

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．