Take the quiz here: http://features.pewforum.org/quiz/us-religious-knowledge/
For example, "Which one of these preachers participated in the period of religious activity known as the First Great Awakening?" and a question asking whether Catholics believe communion wafers and wine become the body and blood of Christ or just symbolize the body and blood of Christ, versus, "In which religion are Vishnu and Shiva central figures?" and a question basically asking which religion observes Ramadan.