Someone didn't pass his exam and is too upset to do anything, you'd better say to him:   [ ]

A. It's less of a problem to be poor than to be dishonest.

B. Don't let yesterday use up too much of today.

C. Tell me and I'll forget. Show me and I may not remember. Let me try and I'll understand.

D. You can't wake a person who is pretending to be asleep.