Hate to get all political here but Forrest was not necessarily the "most brilliant cavalry commander in the Civil War." (Even in the Confederate army, i.e., the losing side, there were commanders like Jeb Stuart and Morgan). More significantly, Forrest is better known for--and historically more important--as one of the early leaders of the KKK. Let's not put lipstick on a pig. On the other hand, to be fair, it must be noted that late in life he purportedly recanted some of his earlier odious racial beliefs. Ultimately, a complex historical figure not accurately characterized as just a "brilliant commander."
Yes, but he still became a Grand Wizard of the KKK. There are good and bad things about all historical figures and we should remember them as they were, relevant to the times in which they lived.
Involvement in the KKK has nothing to do with his skill as a cavalry general. The fact of the matter is that his is one of just a few names that comes into any discussion of the top cavalry generals. Stuart, as you noted, is another but Morgan is not in that class.
He became dismayed by the violence and lawlessness of the Klan and actually disbanded it. The later two incarnations don't seem to offer any second thoughts about their actions. Still, that doesn't affect his ability as a general where men are judged as heroes for butchery that far outstrips the goofballs in the Klan.
Genghis Khan committed genocide and rape on a scale unrivaled before or since (save for possibly Tamerlane). You still can't argue he's one of the greatest generals and conquerors of all time. Forrest was a brilliant commander of the cavalry. The rest is irrelevant for this quiz.
Johnson and Polk were from North Carolina not Tennessee. Polk was born in Pineville and Johnson was born in Raleigh.
Jackson is still disputed but even where most agree he was born isn't Tennessee. However all did have significant ties to the state so maybe the question can be re-worded
I think the question's referring to what state they ran from, i.e. Obama was born in Hawaii but ran from Illinois. So yeah they could probably reword it a little
I think a good bit of trivia to add would be the element named after Tennessee: 'Tennessine.' It's a big deal for the state and a worthy inclusion in their history. (As a Tennessean this is one of the things I'm most proud of about the state)
Jackson is still disputed but even where most agree he was born isn't Tennessee. However all did have significant ties to the state so maybe the question can be re-worded