Plz suggest me which field I choose for my graduatioin

I recently pass my 12th sci. with 88%. As per my marks of comp. exams I will get gov. BDS or Grade 1 b tech college. I'm interest to join IAS. so sir plz guide me to choose my graduation field but my ultimate goal is to crack ias with good score. I have confused whether to join B Sc /BTech/BDS/BAMS