Morbidzbaby , Not only can't anyone choose to be heterosexual or homosexual but also can do nothing in this matter .This means that no one can change nature ,genes.God didin't create homosexualists or lesbians ,as I say before , so no one can change his/herself sexuality.God made only perfect heterosexual mankind.So no one can change his original programme but of course he or she can change his/her life-style.And we know ,as I say before,,that many people have become homosexualists.The same happened in ancient times{Sadom and Gomorrah }But of course we do know that such people can abandon immoral way of life for various reasons.And many have done so. So it is possible to change one's life-style .And We can observe some people who can practice ,in the same time, a homosexual and heterosexual life-style{because they want}They want to experience something new ,new form of sex to break some kind of rutine one and so on.There are many other reasons people do such things.And of course since everyone can abandon such immoral life-style so the lesbians ,mentioned before ,who has been studying for several years with JWs can do the same.
As we very well know, the world places great emphasis on sex life .And ,as I mentioned,many people practice homosexuality and other new form of sex for many reasons ,such as ,for example ,curiosity,experience something new and so on.We can also consider an example from the past when demons as a first wanted to have intercourses with women and they bore to them.The Bible says that the sons of God began to notice the daughters of men.Those angels went taking wives for themselves.And in such way they broke God's law,in the same way as homosexualists do.And we must also say that everything :people, animals, earth and so on that God made was perfect.God created earth for perfect heterosexual mankind .The design of living things is that scientiests often seek to mimic it.But try as he will,man cannot truly duplicate that perfect originals found in nature.We can also say that living things have done everything we want to do ,without poluting the planet or mortgaging their future.We can say wisdom in it. Similar heterosexualists are a God's perfect product .And obviously homosexualists are product of people's lust .So we see that homosexualism is not design by God and obviosly it is not natural.It is only one of human life-tyle.And this bad life-style in some way is similar to poluting our planet or think like this. A man wants to be almighty like God but he doesn't have ability to do that.
So I even quite agree with you in that what you say:
Human sexuality is an inborn trait.
Yes, it is true because Gode made only heterosexual people to have children and be happy.