I think the belief that there is "one true religion" is one of the greatest issues of mankind. When you look at the history of the world, and the hundreds of cultures that are still around today, you'll see that religions are just as various and plentiful as languages. Is there one "true language" sent by God?
I think each culture has the choice of how it views God, or whether it believes in one god or many gods, and each culture has the power of creating and accepting its own Holy book. In the modern world, we lose sight of how many faiths there are because there are just a small set of "mainstream" religions that have been taken up by a majority of the world (Christianity, Islam, Judeism, Buddhism, Hindu).
I believe that the origins of the universe and answers of the soul and so forth are questions that are beyond our earthly reach, so religion is each culture's "best guess" at what those answers are. And there is nothing wrong with that- every unproven theory in science, like the big bang and superstring theory, is really just a "best guess" based on what can be seen, heard, and felt.
But religion has been the cause of so much hate and conflict because people put a frightening amount of faith and belief in their religion. Faith and belief are wonderful things when you keep them within you and among your fellow believers, but once people feel compelled to go straighten the rest of the world out and make them see the world the way they see it, I think it's one of humanity's uglier faces.
So my answer is, if there was one religion sent by God, I'm sure he would have sent it to everyone loud and clear. Unfortunately, if you ask around, it seems God sent a bunch of different peoples of the Earth a bunch of conflicting stories, and that seems very cruel and unusual to me. So I think that, if there is a God, he or she is letting us decide how to handle those tough questions on our own.
So I would ask that you consider rephrasing your question, and instead ask which religion seems right for you. And always allow people their right to decide for themselves what faith speaks to them the most. I think the world would be a kinder, safer place if people took that approach.
And I was very pleased to see so many awesome answers posted for this question. I was really afraid the majority would just shout out their religion point-blank end of discussion, which is insulting and ignorant to the rest of the world, but luckily that was only a small minority. That gives me some hope that people are lightening up a bit. :)