Why Does The Symptom Checker On The Site Start With

Why does the symptom checker on the site start with asking whether I am a man or a woman when the definitions of man and woman are Man: the sex that produces spermatazoa; Woman: sex that produces ova, but also someone whose appearance is female and someone with a female gender identification. So, anyone can be a woman but all men are the sex that produces spermatozoa. There is a biological definition of male, but a social definition of what is female. Would a male who gender identifies as female get the best possible medical advice by clicking the female box on the symptom checker?