To Question or not: That is the question.

[sensei8]

Who's to say that the asked question is dumb or ridiculus? The question wasn't either to the student, that why the student asked. The sensei can disern one way or another, but, imho, that sensei better be correct.

If I discern that the student was not serious in the question, then I'd tell the student to see me after class. Then, I'd place this student back on track as well as inform that student that when he/she is not serious, then they end up waisting time, when that can be better served during class. A student wants to joke around, then joke around before and after class, but never during class.