If you get a lot of unsolicited sales, fundraising, and/or scam calls, I have a suggestion. When I get one of those and if they don't identify themselves or their organization, I ask coldly, "What is the purpose of the call?" Over half hang up without saying anything else.
If they continue by trying to go on with a spiel, I interrupt them and say, "I asked you a question and I demand that you answer it before you go any further." Another 40 percent also hang up at that point.