Answer:
Did you hear about the novice water polo player who was upset because..... his horse could not swim.
Step-by-step explanation:
It is a play on words because water polo is understood as polo that is played in water instead of water polo which is a swimming sport. Some people get these 2 sports mixed. Polo, you ride on a horse, and you hit a ball with a stick. Water polo, you play in a body of water, and you swim, you hit people with your arms (as long as the ref doesn't see!)