Greetings!
I think dejavu has suggested a very good topic, and there are others that are similar that might also work well. Basically, you need to ask yourself if you have a strong opinion and enough good arguments to support your topic. That's your starting point for an argumentative essay, as I'm sure your professor has told you. If you can come up with the same type of question that your professor gave as an example (or even use her example as your topic), you should be fine. If you want more confirmation, you can run your choice by her.
Enjoy writing your essay--arguing can be lots of fun!
Sarah
EssayForum.com
Sarah, EssayForum.com