With caller ID I can see who I want to talk to. Otherwise I just pick up the receiver and put it down again so there are very few rings to disturb my work. I realize I'm dealing with a computer generated call and so who cares if there is someone "real" on the line. All they want is a donation or to taunt you with "Don't tell me you don't want to make money", etc. Boring and invasive but unless the government puts a stop to it, it'll go on and on. Let it go. Life's too short.
I picked up the phone finally after ignoring the call for the last few days. A man asked to speak to the head of the household. When I asked who was calling, he said "a charity". Didn't tell me what charity though. I then hung the phone up.