[stinky613]

Oh I'm not advocating that this actually being used as a captcha. Though, as a thought experiment, I think it would be more effective if you had, say, eight gifs. Instead of an either-or choice you could ask the user to choose all that match a given condition.

I had a teacher who employed "multiple multiple choice" questions on his exams. The question would have some number of choices (e.g. a,b,c,d,e) and you had to choose the correct answers. These questions were tricky because the answer choices could all be wrong (meaning you select none of the answer choices), could all be correct, and any combination of the answers could be correct. It made guessing go from a 1 in 5 situation to 1 in 32. I was not a fan.