The correct answer is: a) Lignite.
Lignite is the lowest rank of coal, and it is the most abundant type of coal found in Meghalaya. It is a soft, brown coal that is formed from plant material that has been buried and subjected to heat and pressure for millions of years. Lignite has a high moisture content and a low carbon content, which makes it less efficient to burn than other types of coal. However, it is also the cheapest type of coal to mine, and it is used primarily to generate electricity.
Bituminous coal is a higher rank of coal than lignite, and it is found in smaller quantities in Meghalaya. It is a black coal that has a higher carbon content than lignite, and it is more efficient to burn. Bituminous coal is used primarily to generate electricity and to produce steel.
Anthracite is the highest rank of coal, and it is not found in Meghalaya. It is a hard, black coal that has a very high carbon content. Anthracite is the most efficient type of coal to burn, and it is used primarily to generate electricity.
Peat is a type of coal that is not found in Meghalaya. It is a soft, brown coal that is formed from plant material that has been buried and subjected to heat and pressure for a relatively short period of time. Peat has a low carbon content and a high moisture content, and it is not used as a fuel.