-Is the man over there your English teacher ?

--No, it ______ be him. He has gone to Canada to study further.

A．mustn't

B．can't

C．won't

D．needn't

七叶一枝花的正名为（）

A．槟榔 

B．牛蒡子 

C．首乌藤 

D．重楼 

E．大黄