Dear aspirant!

According to me and the sources , can pursue MBA after any stream study be it arts commerce or science. So BA in economics and history should not cause a problem. Usually you need to write the CAT examination for getting a seat in the top IIMs .MBAis basically  a 2 year long masters program  so basically you need to have a BAor BBA or BSC or Bcom or Btech degree to get a MBA degree. Hope this helps.