Use your answer to demonstrate your knowledge of the company and re-emphasise your suitability for the position. Give specific examples of things that attracted you to the company, so the interviewer can see that you match their culture and will thrive in the position.
While this looks like a question about you, the interviewer wants to know what you can do for the company and that you are a good fit for the job.
In your answer, you might want to elaborate on your strengths and achievements and how they match the position description. You could also talk about your career goals and the objectives of the company (information from your research). In both these instances, you are explaining how and why you would be an asset to the company.