Solution:Kerala retained the top rank in Niti Aayog's SDG India Index 2020-21 that was released in June 2021.• Uttarakhand, Gujarat. Maharashtra, Mizoram, Punjab, Haryana, Tripura, Delhi, Lakshadweep, Andaman and Nicobar Islands, Jammu and Kashmir and Ladakh were placed in the category of front-runners..