As on 6th April 2015 which of the following cities doesnt have National Air Quality Index?

As on 6th April 2015 which of the following cities doesnt have National Air Quality Index? 

Options:

1) Mumbai

2) Delhi

3) Chennai 

4) Bangalore

Answer:

1) Mumbai

Other Details:

• The ten cities where the National Air Quality Index will monitor air quality are Delhi, Agra, Kanpur, Lucknow, Varanasi, Faridabad, Ahmedabad, Chennai, Bangalore and Ahmedabad.
• Later it will be extended to 22 State capitals and 44 other cities with a population exceeding one million.