The correct answer is (a).
Chhattisgarh is the largest producer of coal in India, followed by Jharkhand and Orissa. In 2019-20, Chhattisgarh produced 199.5 million tonnes of coal, Jharkhand produced 177.9 million tonnes, and Orissa produced 138.5 million tonnes.
The other options are incorrect. Option (b) is incorrect because Jharkhand is not the largest producer of coal in India. Option (c) is incorrect because Orissa is not the largest producer of coal in India. Option (d) is incorrect because Madhya Pradesh is not one of the top three producers of coal in India.
Coal is a fossil fuel that is formed from the remains of plants and animals that lived millions of years ago. It is a major source of energy in India, and it is used to generate electricity, produce steel, and make other products.