Yo mama so stupid, she thought a quarterback was a refund.
Quarterback Refund
Explanation
Explain Bear
Listen up, buttercup! This "yo mama" zinger is all about your mom being so dense she mixes up football terms with finance. A quarterback is a football player, see? But your mom thinks it's money back, like when you return a busted toaster. I'm a bear, and even I know that's dumb!