Expect a little nervousness before your interview. Most will try to help you break the ice. Part of their job is to learn about your personality and interests. Don't try to play the role of high school big shot or future corporate lawyer. As a 17 year old, you're not supposed to have all the answers.
Most interviewers ask open-ended questions to allow applicants to direct the conversation.
Interviewers often use a topic like these to assess the depth of an applicant's thought. If you say that Huckleberry Finn is one of your favorite books, be prepared for 15 minutes on the relationship between Huck and Jim. Come armed with a question. Interviewers usually ask if you have one. Most applicants hem and haw and finally say that, well, maybe the tour answered them all.