How to deal with junk phone calls:

Phone calls from solicitors usually give themselves away by the fact that there is a delay of around 3 seconds after you say "hello" and before the person on the other end replies. That's because the dialing is done automatically by a computer, and they even use the computer to detect that there is a real person on your end (as opposed to an answering machine or fax), before they match your call up with the next available agent. This takes some time. They might even be calling from India, which adds more to the delay.

So if I hear 3 seconds of silence after I say "hello" I immediately hang up. No use wasting any time or energy on these things.

Once in a while, it's a real person from the get-go; there is no automatic dialer and so no delay. So then as soon as I realize the call is a solicitation from someone I don't want to talk to, I say "No, thanks" and hang up.