And a Z for elsehow

since when there were "z"?

https://www.rxlist.com/z_chromosome/definition.htm

Um, there's more than 2

where did you get that from?

My nads

no, where

You're kidding, right?

If you're going to refer to science, at least have the decency and self respect to look it up. Even a simple dictionary definition will do, no PhD required.

Let me rephrase it for you
There are two sex chromosomes that control wether you are male or female. (X and Y)
If you have two X chromosomes you are female.
If you have an X and a Y chromosome you are male.
There you go. Biology class since you never took it.

But what about for intersex people?

That’s the exception. Those people just choose the one their bodies most represent.

Around 1.7% of the population is born with intersex traits.

You call that an exception, there is just as much intersex people as there are people born with red hair

https://www.amnesty.org/en/latest/news/2018/10/its-intersex-awareness-day-here-are-5-myths-we-need-to-shatter/

Yeah, red hair is a mutation in the genes too. That makes it an exception as well.
https://youtu.be/BX1WpL2VlhM

But I have seen plenty of people with red hair in my life

.