Three senior BJP leaders including president J.P. Nadda campaigned in West Bengal on Tuesday and raked up religion as a poll plank. Mr. Nadda, who held a road show and addressed a public meeting in Bankura, wondered why Chief Minister Mamata Banerjee announced a lockdown on the day of foundation stone laying of Ram Temple in August 2020 but lifted it on the day of muharram. Delhi remained the most polluted capital city in the world but India, on the whole, had improved its average annual PM 2.5 (particulate matter) levels higher in 2020 than in 2019, according to a report from IQ Air, a Swiss air quality technology company, specialising in protection against airborne pollutants, and developing air quality monitoring and air cleaning products.