(1) Are the biblical accounts of the resurrection of Jesus accurate? Did this event really happen?
(2) Is salvation found through Jesus Christ, alone? Was Jesus being literal when he said, “I am the Way, the Truth, and the Life. No one comes to the Father except through me” (John 14:6)?
(3) Is sex outside of the Sacrament of Marriage a sin?
And I had been trying to think, is there a set of questions that can be created for Muslims. I think the problem in trying to do so is that the range of possible answers given by Muslims to most questions would actually be quite narrow. Take the third question above (which is the only one of the three that's actually relevant to Muslims). The correct answer, of course, is "yes," which I suspect 99% of the world's Muslim population would agree to. (IMO, you'd really have to be outside of a state of Islam to answer "no" to that question.) And so the third question really isn't a good discriminator in being able to separate Muslims into more distinct groups. Which, of course, is something that's frowned upon in the Qur'an anyway. So I'm not sure such a trio of questions is really possible except for nit-picking into the minutiae of the religion because the basics of Islam are, IMO, pretty universal among all Muslims.