There can be different answers to this question. What I preferred to answer is :
I am looking for a financial growth along with woking for a good company on a trending technology. As I am getting all of this with your company so that's a good choice for me.
Remember :
1. If the compnay is offer you the same designation as that of your previous company then never say during the interview that you want take more responsssibility .
2. If the compnay is offer you the same technology as that of your previous company then never say during the interview that you want are switching for a change.