The correct answer is (d). Bharat Stage VI (BS-VI) emission norms came into effect for all vehicles nationwide on 1st April, 2021. BS-VI is the latest emission standard in India, and it is much stricter than the previous standards. The new norms are aimed at reducing air pollution and improving public health.
BS-VI emission standards are based on the Euro 6 emission standards, which are the strictest emission standards in the world. The new norms require vehicles to emit significantly less pollutants than before. This will help to improve air quality and reduce the risk of respiratory problems, heart disease, and cancer.
The implementation of BS-VI emission standards is a major step forward in the fight against air pollution in India. The new norms will have a positive impact on the health of millions of people across the country.
Here is a brief explanation of each option:
(a) 1st April, 2018: This is incorrect. BS-VI emission norms were not implemented in India on 1st April, 2018.
(b) 1st April, 2019: This is incorrect. BS-VI emission norms were not implemented in India on 1st April, 2019.
(c) 1st April, 2020: This is incorrect. BS-VI emission norms were not implemented in India on 1st April, 2020.
(d) 1st April, 2021: This is the correct answer. BS-VI emission norms came into effect for all vehicles nationwide on 1st April, 2021.