A professor stood before his class of twenty senior
organic biology students, about to hand out the final
exam.

"I want to say that it's been a pleasure teaching you this
semester. I know you've all worked extremely hard and
many of you are off to medical school after 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 opt out of the final exam today
will receive a 'B' for the course."

There was much rejoicing 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 handful of remaining
students and asked, "Anyone else? This is your last
chance." One final student rose up and opted out of the
final.

The professor closed the door and took attendance of
those students remaining. "I'm glad to see you believe in
yourself," he said. "You all get 'A's."