Someone told me about an experience with telemarketers trying to get him to change communications companies, the telemarketer had a phrase like "is that OK/alright with you?" if at any point you say "yes" they record that and use it as proof you signed up to their company. When you get a bill from XYZ communications it will cost $150 for you to get out of the contract. Which I suspect is a good earn, better than the small margin on phone calls. If you do listen to a telemarketer never say "YES".
ba just have a word document template cut and paste the scammers details in there takes 10 seconds .Oldfarts approach of telling them how your syattica is playing up with the weather and fruit preserving is a good one