Catholics. 1.2 Billion. One leader. 17 million converts 2009. Protestants Largest? Anglican 80 Mill. Why?

Because, not to offend anyone, Catholicism is the only 100% correct religion. Almost all other religions branched off of Catholicism when they got tired of sacrificing, so they created their own religion. Anyway, it is written that the Catholic Church will never be wrong. In fact, a pope once died the day before he was supposed to sign a false document.