Don't think of a mentor as someone who is only at work, but try to look at the people in your life that you consider important. As long as the person has offered you advice that made a difference in your life, that person could very well be considered a mentor. Take some time before the interview and think about someone who has helped you make progress in your career or personal life. Think about what they offered, and try to form that into a short two-sentence answer. If you won a big award or achieved something outstanding, there will always be people who helped you to achieve that goal--you can credit them as your mentor.

"My professional mentor is an advisor from my college. At first, I met with her to plan out my college courses. She has a degree in engineering and soon became a good friend and mentor. I've been speaking with her for the past two years, following graduation, to make sure that I'm taking the right steps for potential future advancements in my career. For example, she helped me get the right training in prep for taking the industry certification exams and I was able to pass on my first attempt, which is very unusual for most in our industry."