If I only need to get one question right it doesn't take many questions before (3/4)^n is smaller than the chance the professor, for whatever reason, avoided C.
I disagree. I'd put that probability at 0 after n=7.
In fact, according to the recent reddit thread, some test designers are encouraged to enforce equal proportions of each option. While stupid, it lowers the threshold to n=3 or so.
In fact, according to the recent reddit thread, some test designers are encouraged to enforce equal proportions of each option. While stupid, it lowers the threshold to n=3 or so.