You can pretty much assume access to the Drow race, at least as safely as you can assume access to anything else that’s in the PHB. Which is to say, chances are it’ll be fine, but it doesn’t hurt to double-check, and be prepared for the possibility that the DM will say they don’t think it’s a good fit for the campaign.
Are you talking about if you happen to encounter one as an NPC and ask it really nicely?