Hello Piyush. B.A. Economics is a three year graduation course having 6 semesters. The top institues offering this course are Loyola College Chennai, Christ University, Presidency College Chennai, Madras Christian College and Fergusson College. The colleges mentioned above require minimum score of 50% in your 12th examination. The admission is obtained on the basis of entrance exam and interview of that particular college. Saint Xavier's college of Mumbai is also one of the best colleges of India for B.A. No one can guess the criteria or merit list of any college priorly. So you need to apply for all colleges where you would be comfortable to study. Based on the merit list of all colleges you'll get your best suitable college.