Anytime you come around to the end of the interview, you can expect a question like this to arise. How you answer will inform your interview of how engaged you were during the interview, how thoroughly you prepared for your interview, and whether you ask any questions they already answered or which you could have easily answered on your own with some basic research. So, try to make yourself memorable by asking questions they don't hear every day, or questions that exemplify your work ethic and showcase how thoroughly you prepared for your interview.