jumping blonde

A blonde, brunette and a redhead run to the top of a burning building. Below, a few firefighters are holding a blanket telling the redhead to jump.

When the redhead jumps the firefighters snatch the blanket away and she hits the concrete.

When the firefighters ask the brunette to jump she jumps and again they pull the blanket away.

When the firefighters ask the blonde to jump she replies, "I don't trust you, so just put the blanket down and back away."