Here interviewer want to know that in what ways you think you can contribute to their team. The interviewer could have rephrased this question, "Are you able to see the bigger picture?" They're searching for evidence that you understand the purpose and goals of your department as a whole and how your role fits into the big scheme of things. They want to know what you will be bringing to the table and how the company will make the right decision in hiring you. Therefore, you need to have an appropriate and convincing answer to this question and that can be given by discussing your past accomplishments and your future ambitions. Here you need to just highlight any significant contributions you have made to a company, or any recognition you have received in previous positions and do not just list duties of previous jobs you have held without stating how you contributed to them.