---Hello! Is that Mr. Wang speaking?

---Yes. _______

1. A.
   Who’s that?
2. B.
   Who are you?
3. C.
   I’m speaking.
4. D.
   I’m Mr. Wang.

　　--Hello! Is that Mr. Wang speaking?

　　--Yes, ________ ?

[　　]

　　--Hello! Is that Mr. Wang speaking?

　　--Yes, ________ ?

[　　]