What options does one have to defend themselves against intrusive callers?• The Do Not Call list (Federal or State)Works, but is effective against ONLY 'legitimate' telemarketers. Political callers, surveys and some other callers are exempt. Scammers ignore the DNC list.• NoMoRoboA system offered by some telephone providers, to help automatically block robocalls. Google 'nomorobo' to see if it works with your phone provider.• Shouting, screaming, swearing at the callerNope. Does not stop calls. May make you hoarse, and will disturb nearby people.• Call blocker app, device or serviceCould be a good choice (even though the scammers can use fake phone numbers), and some apps are free!Google 'call blocker' for more information, or check your favorite online sales site for a list.http://gg.gg/blockersYour phone provider may also offer blocking services. Check their web page for information.If you cannot use any of the above defenses, then:• Do not answer calls from unknown numbers ... let them go to voicemail or answering service• Do NOT return calls from unknown numbers! All that does is verify your phone number! And, in some cases, those return calls may cost $20 or more to complete. http://www.consumer.ftc.gov/blog/one-ring-cel ... ing-your-wallet• If you have a 'dumb' cell phone, assign the scammer's number to a group named 'scammers' (or similar). Then, assign a silent ringtone to that group.