Delhi is the most polluted city in the world. That's common knowledge today. But did you know that 13 of the 20 most polluted cities in the world are right here in India? In the third episode of our special series on air pollution - Clean Air, My Right, we take a look at what is contributing to this mess. How did our cities get this polluted?

http://www.ndtv.com/video/player/clean-air-my-right/how-did-india-s-citi...