The best argument is not to argue at all. Those complaining are usually trolls feeding on your irritation or inherently intolerant people who will never think freely enough to consider any of your points - and the more you will argue, the most they will curl up in their own speech and be deaf to yours. Easy to identify: those who come at you with a question, are usually those whom you will be able to politely and intelligently have a debate with, all the rest should be blocked. Never forget also that it's those who advocate for love the highest who are the most hateful (I'm looking at you, Church).
The best argument is not to argue at all. Those complaining are usually trolls feeding on your irrit