How do you know if a snowman is a girl or a boy?
A: Snowballs.
How do you know if a snowman is a girl or a boy?
A: Snowballs.
Listen up, genius! The punchline is "snowballs" which is a play on words for... well, bear stuff. Basically, the joke is saying that you can tell the gender of a snowman if it has snowballs, duh. The joke creator is probably not that smart since it is a pretty simple observation.