Another British show where silence was a virtue was Michael Miles' "Take Your Pick," which ran in the 50s and 60s on ITV (and allowed producer Rediffusion to fill the later hours with serious documentaries and Harold Pinter plays). The show opened with "The Yes-No Interlude," where each contestant came out--if they could make it through Miles' interview without saying "yes" or "no" once, they'd get to play the game. Of course, his questions were designed to elicit those words without thinking--and if they did say "yes" or "no," announcer Bob Danvers-Walker, who was standing behind them, would raise his miniature gong to their ear and bang on it, eliminating them from the game.
If you recall the Python sketch where John Cleese plays the oily emcee being patronizing to the "Pepperpot" playing for "tonight's star prize, the bump on the head," the sketch was inspired by "Take Your Pick." (To fill in the details, on the real show the contestant who went to win the quiz would them get to pick from 14 boxes, hoping to find the star prize instead of the booby prize.)
The show was revived briefly in the early 90s on ITV, hosted by the veteran entertainer and current Regis to Melanie Sykes' Kathie Lee/Kelly on ITV daytime Des O'Connor.