Choose something your comfortable with.
I chose a topic from a rotation I recently had. Some programs specified topics. Either way, show enthusiasm and don't be boring. If you take a somewhat stale topic and make it interesting and informative that can speak a lot about your communication skills. Make sure to just answer the "so what?" question regarding your presentation.
A lot of the presentations that are part of your interview has to do with assessing your skills and demeanor and how you may handle a tricky question.