Why should some extremist evilvangelical get to limit the question to only “...one source...”? Why should any candidate have only one source of direction or inspiration?
Despite your looney assertions to the contrary, the Bible and Book of Mormon are not contradictory.
I didn't say that they were, although in fact the Book of Mormon provides a very different version of history from what any Protestant or Catholic Christian would teach. What I said was that Romney ducked the question and papered over the differences.
If, for instance, if an Evangelical Protestant asked me as a Catholic whether I gave the ultimate authority to the Bible or the Magisterium of the Church, I would reply that the two are mutually supportive. Some things that the Magisterium teaches are not specifically in the Bible, such as the Assumption, but they do not directly contradict it. A Protestant might well disagree with that, but at least it would be an honest answer from the Catholic perspective. I don't think Romney's answer was really honest, because he was trying to duck the question.