F: Did you lock the doors? ,M: All except the back door. I left that open of for Tim. He took the dog out for a walk.
(A) F: Why did you make Tim lock front door? (B) F: You didn't lock the front door because Tim is walking the dog, did you? (C) F: I’m sorry, I didn’t catch that. Would you mind speaking more slowly? (D) F: You've locked all the doors. Tim must be knocking at the door.
C