A study from the Pew Forum on Religion and Public Life found that Americans who don’t believe in God scored better on a religious study quiz than those who identify with a specific religion.
The U.S. Religious Knowledge Survey, a nationwide poll of 3,412 Americans age 18 and older, found that out of 32 questions related to various religions, atheists and agnostics typically got the most correct responses. Jews and Mormons also scored higher than Protestants and Catholics.
However, while atheists and agnostics performed highest on religious questions overall, on questions related to Christianity, Protestants and Catholics out-performed all other groups. So, basically, they know more about their own faith than about those of other religions. For those who want to test themselves, a shorter version of the quiz is here.
And this is how you would have to administer the test as a call operator!!
See the Catholica Forum Discussion here