survey
A psychology student is conducting a survey to study the masturbatory habits of males. She approaches the first man, and says "Excuse me sir, I'm conducting a survey, and would like to know: what do you hold in your left hand while you masturbate?", to which the man replies, "A remote controller, for the DVD".
She then approaches the second man, with the same question. He answers "I've got a magazine", and she notes down his answer.
She then approaches a third man, and asks him what he holds while he masturbates, to which he answers "A bar of soap". Bemused by this, she asks why.
"I'm bathing the kids."