Both - people are born with certain potential, which can be damaged in utero if the mother takes drugs or alcohol, at birth from injury, and in childhood from malnutrition, poor upbringing, etc. Or the potential can be enhanced through good education and upbringing, and personal endeavor.
When it comes down to it, you are admitting people are born gay.
I am only saying that some VERY few people - who have, for instance, genital malformation such as hermaphrodites, have the potential for some kind of sexual dysfunction due to birth. But since homosexuals are roughly 2% of the population, and maybe a tiny percentage of THAT have possibly some kind of SSAD from birth, this is a tiny, tiny percentage.
What you are saying is that they could resist if they wanted to.
I am saying that everyone has desires going through their minds at some point in their lives that they don't have to indulge. Some people (for whatever reasons) have difficulty with different cravings or desires. And a funny thing is - the more you indulge a desire, the more it haunts you. The more you ignore it, the less power it has over you.