Slippers.
or
Stairs.
or
Three. One to climb the ladder while the second kicks the ladder out from under her. And the third to say, "I knew that was too high for you dear."
or
100: One to do it and ninety-nine to say "I could've done that."
or
Silly, WASPs don't screw in a light bulb, they screw in a hot tub.
or