Yes, "black" is politically correct, provided you are not referring to African-Americans. "African-American" would be wrong when referring to someone from, say, Jamaica. "Black" might be the...
mail carrier (if they deliver mail) postal clerk (if they work inside the post office) postal worker (if you don't want to be specific about their job assignment)Politically Correct Terms Database |...
The word incarceration is used frequently. We incarcerate people who have broken the law. They are incarcerated. We use incarceration as a deterrent and as a consequence.
Political correctness is a modern invention, so to answer that question is impossible because there wasn't the curbs put on people's speech, art, or thinking that is done today.