Tell him if he ______ speak to me so rudely again, he'll be sorr

Tell him if he ______ speak to me so rudely again, he'll be sorry.
A、need
B、must
C、would
D、should
【正确答案】：D
【题目解析】：该题考查情态动词。此处要填的词用在if从句中指将来，故要选择should。