"It" is never ever appropriate and is deeply offensive. How would you feel if someone called you, 'it'? Well, trans people are not somehow superhuman and immune to that feeling too - so don't use it.
Saying "just pick a gender to call a trans-person " may be a bit controversial as some people don't like
people
"assuming your gender" and all that, but a couple of trans friends have said, "the awkwardness of people struggling over their gender is so painful. I'm wearing a dress, what the fuck do you think I want to be called??" So yeah, of course, the if person tells you that they prefer to be called 'him' or 'her' then call them that. The default should be the gender they are displaying.
Now, what if you aren't sure? Well, unfortunately, all standard singular English pronouns have a gender, There are other pronouns such as 'per' to refer to a person without gender. I have always felt this verb made me sound like a guy studying feminism. People tend to react with surprise and equal discomfort to odd words and that in itself draws more attention to the subject. Instead, I greatly prefer using, 'they'. Everyone knows what it means, it's common English and it just flows.
Ok, next: discussing if they are taking hormones, surgery, and the status of their genitals...never do
this when you just meet someone. Seriously. If you just meet someone and they start quizzing you if you are circumcised or if your pussy is completely shaved....that is utterly inappropriate. So just don't fucking do it. Hormones and surgery are deeply personal and their medical status, just like any medical condition I have, is none of your business. Especially if we just met!
Now can you ask about their genitals? Well fuck, anyone I sleep with, I discuss shaving and other
genital issues (like tendencies for him to turtle or gather lint if it is brightly colored)....so if you are getting intimate with the person and considering having sex with them...yeah, that's fair to ask what you're getting yourself into. But generally, that conversation doesn't happen with everyone and certainly not within minutes of meeting the person.
On to bathrooms: trans people go in the bathroom associated with their gender. So if they are dressed as a woman, it's the woman's bathroom. Is there an issue with trans people molesting people because there are 'men' in the women's bathroom. No. Probably the worst thing for a trans-woman in a bathroom is someone calling them a man and they definitely don't want to call attention to that biological fact which is so different from their true self. And honestly, how much do you really want to interact with strangers in any bathroom? Just leave them be and they'll leave you be and everyone will get on with their day.
