Probably religion. I like to keep things light.

I'd talk to all three of them at the same time, like a slut

Charm the vegan so I can eventually eat them

Politics, because I can actually hold a proper conservation.

I start talking to them all about feminism and don’t stop until they leave the room so that I can be left alone to eat my dinner in peace.

Definitely the snobby vegan. The politics one I'm bound to disagree with on some things and that would irritate me. And if
I spoke my truth it would irritate him/her. The religion one I'm bound to disagree with on everything, so same only more so. Vegans, otoh, are the salt of the earth and they have the right to be snobby. ;)

The vegan, to educate him that extreme vegans are a danger to the movement. I am vegan myself so he will listen to my ass.

I think I would make the politics talker talk to the religious guy and soon they will fight while I listen to the snobby one and have all their drinks since they are immersed with other things.

I would happily take any one of them. It is one of my greatest hobbies to argue with people who have strong beliefs. Usually I start by asking harmless questions about what they believe and follow up on the answers with questions that get increasingly uncomfortable. I proceed doing this without even mentioning what my own stance is, just to see if they start being incoherent or inconsistent or ad hoc. (They always do). I keep doing this until they do not want to talk to me anymore and that is how I make new friends.

Politics for sure. I'm not vegan so I can't relate and they tend to be the most self aggrandizing jackasses, so they're out. Religious people are pretty unbearable too. I've gotten along just fine with people who don't agree with me politically in the past so it can't hurt.

I'll take the vegan, atleast this discussion hasn't been as omnipresent as politics or religion over the years so there's still things to learn.

The vegan for sure, the politics person is a crapshoot, who knows what they believe, same with religion - at least I KNOW the vegan is going to eyeroll every time I even look at the ranch dressing and I can compensate