A professor was going to hand out the final exam, standing in front of his class of twenty senior organic biology students. He was saying to them, "I'd like to say that it has been a pleasure teaching you this term. I know you've all worked extremely hard and many of you are offer to medical school after summer. I know you've all worked extremely hard and many of you are off to medical schoolafter summer. So that no one gets their GPA messed up because they might have been celebrating a bit too much this week, anyone who would like to choose not to take the final exam today will receive a 'B' for the course and can go out of the classroom now."
There was much pleasure in the class as students got up, walked to the front of the class, and took the professor up on his offer. As the last taker left the room, the professor looked out over the few remaining students in the classroom and asked, "Anyone else? This is your last chance."
One final student rose up and chose out of the final. The professor closed the door and took attendance of those still remaining. "I'm glad to see you believe in yourselves," he said. "You all gat 'A's."