Which city of India was ranked as the world’s most polluted in the ‘World Air Quality Report 2019’ compiled by IQAir Air Visual?

According to the 'World Air Quality Report 2019' compiled by IQAir AirVisual, Ghaziabad in Uttar Pradesh, India, was ranked as the most polluted city in the world, with an annual average ${\text{PM}}_{2.5}$ level of $110.2\mu {\text{g/m}}^3$.