Hyderabad has around 40 % Muslim population right from the time of Nizam. So don't blame North Indians for Urdu in Hyderabad. I am a Telugu guy, but if I want to interact with Muslims in Hyderabad who don't know Telugu, then I have to use Hindi. So stop putting the blame on North Indians. Dude, I lived in Hyderabad for more than 15 years. Don't try to fool me about Hyderabad.
