Which is politically correct-Black or African-American?

I am an equal supporter of both Hillary and Barack so I am a happy camper.

But now that race and gender are part of the political discourse, I don't want to offend anyone.

I hope this isn't a stupid question, as I've noticed the MSM uses African-American mostly and it comes across a bit negative to me and I would like to know from those who really know what is the preference?

Please believe me when I say this is an honest question from me. Am I the only one wanting to know?

I know it use to be okay to say black guy, but it seems that has changed and I missed the memo?

Is there a preference? Please set me straight. Thanks.