Good morning, may I speak to Mark, please?早上好,我可以跟马克说话吗?( )请讲(

Good morning, may I speak to Mark, please?早上好,我可以跟马克说话吗?( )请讲(我就是)

A.Who’s there?

B.Who’s speaking?

C.Who are you?

D.Who wants to speak to Mark?

正确答案是B