There are numbers of people asking about/wanting to add third option in Sex: "Transgender".
Sex: Female or Male, period. It's the law of nature. Stop and think, is there Transgender sign when it comes to water closet/restroom?
Transgender is "Sexual Orientation" and it doesn't necessary mean who you want to sleep with but who you are. I am/you are... Bisexual, Gay, Intersex, Lesbian, Questioning, Straight, or Transgender.
If male becomes female then "she's" a female. If female becomes male then "he's" a male. He/she can always change Sex option. Simple as that.
Hope this helps.
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