You seem to be really fixated with the gender binary. Why is that? I know many people who do not fit into a strict binary and even for those of us who do being so fixed on it is harmful. Life exists on a spectrum, and that’s a beautiful thing.

Most are pretty interchangeable, but if you go for 'define yourself', then you'd have to change it to something like 'as whatever you want'/'however you want', etc. I'd have a slight preference for 'male'/'female', etc over 'man'/'woman', etc, as the point you're making applies to boys and girls as well as men. I'd also go for 'And this cannot be changed' (this sounds more final and literary).

Here's how I would write it, with my own style and grammatical preferences, not bound by the binary options that you've requested we choose from: On gender determination You can declare your identity all you like, drink hormones, cut & paste organs, etc. But a man will never truly be a woman, and a woman will never truly be a man. Because a man is male at DNA level. Every cell in his body contains a Y chromosome, while not a single cell in a woman's body has such a chromosome. And there's no way to change that. But! I would not actually write this, as it's not politically correct (it could get you 'cancelled'), and I'm not sure if it's technologically correct either (I don't know how advanced gene editing is, or will be in future).

Most of your options are synonymous and interchangeable. The pairs that are not synonyms are male/man and female/woman. But, I can’t choose for you which ones to use, because in this piece of writing, you are expressing an opinion. Some people believe in a rigid gender binary, while others disagree. To clarify how these terms are typically used in academic and professional settings: male/female are scientific, biological terms, whereas man/woman are social terms and identities. For example: Our cat gave birth to two male and two female kittens. A bar mitzvah is a ritual in Judaism in which a boy becomes a man.

This never been a necessary question to be asking you should know yourself better than anybody else ☺️