--- John, where are the cookies? Don’t tell me you ate them all!

--- ______ I couldn’t help it. They were so good.

A．Yes, I did.

B．No, I didn’t.

C．Yes, I have.

D．Why? Sounds strange!

—_____ is my bag?

—It's on the sofa.            [ ]

A. What    

B. Where    

C. Why     

D. How