Don't be too confident when answering this question! Tell the interviewer about the qualities you possess as a leader. Competence, motivation, intelligence are all skills you possess as a leader. Have you help a supervisory role before? Have you had people work for you? What would they say about your leadership style and qualities? Don't leave out the importance of being a good follower. Good followers learn to read people and understand what upsets and motivates them and how to get along with those who have differences while not ignoring those differences.You can't be a good leader if you aren't a good follower.