【单选题】

A: Haven't we met somewhere
B: No, I don't think so.
A: Aren't you Kevin Grant
B: No, my name's Greg. Greg Brown.
A: ______

A．I've had enough, thank you.

B．I'm sorry, but I've got nothing to let.
C．Oh, I'm sorry. I was positive we'd met before.
D．I think otherwis