I answered already. Firstly you go to IIT madras and see, Reddys and Naidus are the biggest group. Then only bramins. Bramins took to english first so they came to IITs . That is all. Nowadays, you dont find much of them. Most are gone already.
Got it? Now tell us, why is that out of 400 private colleges, 90% are run bY OBCs?