sorry if this is a stupid question but is it ever okay to ask someone what their biological sex is? like maybe if you’re close enough or they’re open enough and you’re just curious or whatever would that be acceptable or is it considered rude?
there is no “yes” or “no” answer to this question.
how a person will feel about a personal question like that is entirely dependent upon the the person being asked, the relationship that the asker has with that person and the context within which the question is being asked, among other things.
ultimately such information is none of anyone else’s business and it’s up to the person being asked to decide if they feel like disclosing such information to you.
if for some reason you feel like you cannot keep such a question to yourself, the best you can do is ask as politely and respectfully as you can, choosing your words wisely. keep in mind that you are not entitled to an answer. in fact, do not be surprised if you don’t get one at all or if the person is offended by you asking. they may not be offended, but you never know.
use your best judgement to decide whether asking is a good idea or not. it’s a question that is deserving of due consideration as it is not a question that should be asked lightly.
p.s. saying “assigned sex (at birth)” is preferable to saying “biological sex” as the latter suggests that a person’s actual sex (and/or gender) is not who they ‘biologically’ are, which is often an argument used to invalidate trans and non-binary people.