Both. Some people are born with it and others develop it through traumtic experiences.
Yeah I said it multiple times that yeah sure in the most literal sense its a choice in the same way that you choose not to get up from this computer right now and not murder the first person you see. But killing someone randomly is probably not something you would do or is invading your thoughts, so you aren't really choosing not to do it you just aren't gonna. If fukking nikkas is on your mind but you try to suppress those thoughts as soon as they come in, or if you can see yourself fukking a nikka but choose females and even if you never indulge you are at least somewhat gay. Nobody who is actually repulsed by the same gender is going to fukk them, no matter how much they told you they thought it was gross.
The same way I didn't have to "learn" to like women, they don't have to either....They just know. I remember the first girl I looked at like THAT in 6th grade, too young to even really understand what it was.

