Mark the letter A, B, C, or D to indicate the sentence that best combines each pair of sentences in the following questions.
You criticized your son before his friends left. It was wrong of you to do that.
A. If you had criticzed your son after his friends had left, he wouldn't be so upset now.
B. Your son must have been embarrassed when you criticized him in front of his friend.
C. You should have delayed criticizing your son until after his friends had gone.
D. You must be careful not to embarrass your son when he is with his friends.