Don't feed the trolls. Report, block, move on
Very good advice. But if you have some sort of personality defect that makes you occasionally engage with trolls like I do, here is some additional advice:
Make your comment less effort than the trolls. Don't argue every point. Focus on their weakest point.
Essentially, if you can't resist responding to a troll because you're an idiot like me, make it like one short sentence where you point out their biggest mistake, and then if they respond to you and you respond back, keep doing that and never let them change the subject. At least you're causing them to waste effort.