Oh, I always pick up. Usually,, if you ask them if they have ever heard of the do not call list, they can't hand up fast enough.
If that doesn't work, I kindly ask them to remove my name, useing every 4 letter word that comes to mind, like the one this morning. He couldn't hang up fast enough.
I actually had one of these bozo's tell me I had offended him. Hey, he called me, not the other way around.