What is the best question you have ever been asked about your world?

I've been lurking on this sub for a while now and I've noticed a lot of questions like "What is the worst question you have ever been asked about your world or lore?" and "What is the weirdest question someone has asked about your story?" and thought that I would turn it around.<br><br>If you have submitted your work to be reviewed, beta read, critiqued, etc. what is the best question you have ever been asked? Which one really made you have to think a lot about your world as a whole and how you build it? What is the best question that has sparked even more new ideas and worldbuilding in your head?