Hey.

Your choice of college will not matter much if you aspire to become an IPS officer. To be eligible for UPSC exams you need to posess any undergraduate degree. If you're interested in BA Political Science, then it's a good choice. You will take to start preparing along your degree and take the exam in the final year and after completion. You should look for a colleges which will be comfortable along with your prep for UPSC- Location wise, time wise. It won't affect your preparation much. People in various universities/ collages aspire for the same like- Delhi University, Jamia Milia, JNU, Panjab University, University of Mumbai, Osmania University, Christ University etc.

Best of luck