Answer: Everyone, all together now..... Mathew, Mark, Luke and John.
Many years ago I was at a typical JW party get-together and they, of course, played your typical JW bible games. It was a contest to see who could answer questions drawn from a hat.
One of the questions they pulled from the hat was"What are the Four Gospels of the bible?".
You should have seen it... dead silence with everyone looking back and forth at each other. There were at least 100 JWs there. I though to myself: "You've got to be kidding, am I the ONLY person here who knows the answer to this???" I rose my hand and gave the correct answer to the great astonishment of everyone there. They were aw struck that someone could possibly know such a "deep thing of the bible".
That is a question you ask a young child in Sunday School... but "Gawd's Chosen People on Earth" didn't have a clue!
Did you come across any other piece of information that every Christian would know but JWs didn't have a clue?