I'm not sure who started this one, but it has gone virial like a cat playing a piano.
There are stupid questions, lots of them. Just watch the news. They are always asking questions about stuff that doesn't matter when they have limited time with an important guest.
But the biggest offender, in the classroom is the I-Just-Said-That question. If you're not paying attention and you ask a question that I just explained, that, my friend, was a stupid question.