How??? I can show you studies that have a 60% concordance rate. It DOESN"T mean they are right or wrong, only that they were accurate for that sample that day.
What ALL our studies don't have is an ability to be replicated over and over. If you can't answer why that is you have NO credibility to impose your study over any other period.
If doctors/scientists/researchers can't do this, why would you expect that I could? At least I'm taking all studies into consideration. Most studies, espeically recent studies, seem to suggest that there's a biological component to sexual orientation. That's a long way from being conclusive, but neither is it dismissive as you seem to suggest.
Researchers may never find a 100% definitive cause of sexual orientation. Even if they did, I have no doubt you'd find a way to impugn the findings.
To simply tout studies that agree with your argument and reject studies that tend to challenge your position, as you seem to be doing, is intellectually dishonest. Or, in other words, you're fooling yourself.