Economics

Yes, it is very nice to pursue interior designing course along with BA in economics. But, you should be sure about your interest. If you don't have interest in doing design then you should not do this.

Yes, you can pursue M.Sc in economics.

Hi Kavya,
Ph.D admissions are not only based on the scores. You must be accepted by a supervisor, before you can commence your research work.
Below mentioned are some of the top ranked universities for economics in the world:
1. London School of Economics and Political Science (LSE).
2. Princeton University.
3. University of Chicago.
4. University College - London.
You can look for average ranked, but a reputed one like:
1. Maastricht University.
2. Michigan State University, etc. for better chances.

Based on your educational qualifications and interest, you are advised to pursue Ph.D through distance from IGNOU or AMU-AIMA.