English. Easy choice. I prefer a simple two-language formula for all official communications in India. Local+English. There are plenty of languages that English is swallowing up. They are mostly in UK itself. Like Gaelic, Welsh, etc. Not any Indian language.
Hindi is swallowing up languages too. All those languages are in the so-called "Hindi belt". I am not all that concerned about either English or Hindi replacing other local languages. My bigger concerns are legal and economic hurdles placed by Hindi imposers. I'm OK with teaching and requiring English though. Because whether they like it or not, English has become the world's language of knowledge. Especially in computer science. Ruby was developed by a Japanese person, Lua by Brazilians, Python by a Dutch, the Linux kernel by an ethnic Swede. And yet, the best documentation for these is in English.
I'm not an English fanatic. If I were around a few centuries ago, I would have advocated Latin. A couple of millennia ago, I might have advocated Sanskrit in India.