You've limited yourself by picking just two choices because there are probably many that you never even thought of. Those might involve location, financial or family matters, or a host of other things.
If there is a majority, I suspect the reason is neither of those two. I would guess that most people who go osteopathic apply to both osteopathic and allopathic programs because the want to improve their chances for acceptance. I don't think that most really care where they go-- they just want to be doctors.
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