What's the difference between a girlfriend and a test? There isn't one. You cheat on both.
Do you really think this is something you should say about women?
Yes I do. Just because it's a joke doesn't mean that I don't believe it.
Making a joke that compares a woman to a test is pretty dehumanizing to women. Women are humans and should be treated with the same respect given to men. Try to come up with less disrespectful jokes in the future.