Your choices were the following:

• (a) Call for help.
• (b) Laugh.
• (c) Break the other leg.
• (d) Pretend you're a doctor and try to set the leg.

(a) is incorrect because it adds nothing to the humor of the situation. (b) is not the correct response either, because although this situation is admittedly funny, your goal here is to escalate the humor, not cash in on it. (c) is an appropriate humorous response because it causes pain. However, (d) is the correct answer, because pretending to be a doctor and monkeying around with the broken leg is both an untruth and a cause of pain, so it is more funny than response (c).

Special Case: If you are a doctor and answered (c) to this question, you may count your response as correct. In this case, (c) is the correct answer, because response (d) would not be an untruth and would cause much less pain.