A snail because it carries it's home.
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
Five. One to screw it in and four to tell him how bitchin' he looked doing it.
or
One's a spineless, poisonous blob. The other is a form of sea life.
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Because the chicken was on vacation.
or