单选题 — Who's that speaking?
— ______.
[A] I am Jack [B] This is Jack speaking [C] Jack is me

【正确答案】 B
【答案解析】考查习惯表达。Who’s that speaking是打电话时的用语，指“请问您是谁”；回答时用This is sb．speaking，意思是“我是…”。