Correct Answer : Option (B) - Delhi, India
According to the data from air quality and pollution city tracking service from IQAir, a Switzerland-based climate group, Delhi, Kolkata and Mumbai are among the top ten most polluted cities of the world. Delhi topped the list with AQI at 556, Kolkata and Mumbai recorded an AQI of 177 and 169, respectively, at 4th and 6th position. The cities with the worst AQI indices also include Lahore, in Pakistan, and Chengdu, in China.
Here are the ten cities with the worst air quality indicators and pollution rankings, according to IQAir :
* Delhi, India (AQI: 556)
* Lahore, Pakistan (AQI: 354)
* Sofia, Bulgaria (AQI: 178)
* Kolkata, India (AQI: 177)
* Zagreb, Croatia (AQI: 173)
* Mumbai, India (AQI: 169)
* Belgrade, Serbia (AQI: 165)
* Chengdu, China (AQI: 165)
* Skopje, North Macedonia (AQI: 164)
* Krakow, Poland (AQI: 160)
About the IQAir :
* IQAir is also a technology partner of the United Nations Environmental Program (UNEP).
* An AQI between zero and "50 is considered - good", "51 and 100 - satisfactory", "101 and 200 - moderate", "201 and 300 - poor", "301 and 400 - very poor" then 401 and between 500 is considered ‘severe’.