Mr Bush is on time for everything. How ______ it be that he was

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
【正确答案】：A
【题目解析】：can表示可能性。布什先生按时做一切事，他怎么可能开幕式迟到呢?答案是：A。