This is an actual CAPTCHA I was shown when trying to log into PayPal.
As an actual human and not a bot, I had no idea how to answer. Is this a joke? (Seems not.) Is it a Magritte-like existential question? (It’s not a bicycle. It’s a drawing of a bicycle. Actually, it’s a photograph of a drawing of a bicycle. No, it’s really a computer image of a photograph of a drawing of a bicycle.) Am I overthinking this? (Definitely.) I stared at the screen, paralyzed, for way too long.
It’s probably the best CAPTCHA I have ever encountered; a computer would have just answered.
(In the end, I I treated the drawing as a real bicycle and selected the appropriate squares…and it seemed to like that.)