The correct answer is: a) Anthracite.
Anthracite is the highest grade of coal, with the highest carbon content and lowest moisture content. It is a hard, shiny coal that burns with a very hot flame and little smoke. Anthracite is found in only a few places in the world, including Nagaland.
Bituminous coal is a lower grade of coal than anthracite, with a lower carbon content and higher moisture content. It is a soft, black coal that burns with a hot flame and some smoke. Bituminous coal is found in many parts of the world, including the United States, China, and India.
Lignite is a lower grade of coal than bituminous coal, with a lower carbon content and higher moisture content. It is a soft, brown coal that burns with a low flame and much smoke. Lignite is found in many parts of the world, including the United States, Germany, and Australia.
Peat is a type of coal that is not yet fully formed. It is a soft, brown material that is found in bogs and swamps. Peat burns with a low flame and much smoke. It is not a commercial source of energy.