I thought the funniest joke, according to that study, was this:
Holmes and Watson are out camping. Holmes stares up at the night sky and asks Watson, "What do you deduce from seeing the stars?" Watson answers, "Well, there are billions of stars out there. And even if only a tiny percintile of them contain planets, and a tiny percentile of them contain habitable planets, and a tiny percentile of them contain water, then there must be life!"
Holmes responds: "No, you idiot, someone stole our tent!"
I actually didn't find this one funny at all, but I thought this was the "World's funniest joke".