I think most questions, if the intent is sincere, are okay. Two questions that I don't find very fun to answer are:
(1) 你的小孩是否混血兒? For the English speakers, this means, "are your children of mixed race". I am okay with the question, but my kids find this very annoying.
(2) 你覺得臺灣是否中國的一個部分? That is, do I think Taiwan is part of China. I don't have a strong opinion either way. I have lived in both places, and I do know (for sure) that Taiwan is a very different society than China. Not that one is better than the other, just different. I suppose logically, if Taiwan is historically part of China, then the United States is part of England (or France).