Hello, could I speak to Mr. Smith, please?您好，我找史密斯先生( )您是哪位？

Hello, could I speak to Mr. Smith, please?您好，我找史密斯先生( )您是哪位？

A.Who are you?

B.Who’s there?

C.Who could I help?

D.who’s that speaking?

正确答案是D