I enjoy questions that don’t have obvious answers. Not necessarily because I don’t know the answer (there are hundreds of thousands of those), but ones where several very similar answers all make a bit of sense. The multiple-choice question, where all four options have valid aspects to consider. Sort them all, over the matter of a few minutes or weeks, until an answer becomes obvious. Two reasonably thinking adults might come to different reads on the situation, You do the homework, come up with your preference, and future declares who was right. Toss in a few variables that I have no control over, and my mind can run in a virtual loop for three weeks until the problem is solved.