Don't answer these calls because once they know it's an active number they will sell your number to other scammers. If you have a blocking function on your phone, use it. My phone blocks up to 250 numbers. You can also hit the talk button and immediately hit the end call button. This way it disconnects them and they don't get an answering machine or a voicemail, which also shows it's an active number. Someone needs to put a stop to these morons!!!
Won a cruise (supposedly), just needed to fill out a quick survey after which they would give me access to my cruise winnings. Did not press one to continue with the survey. Disconnected the call.