The correct answer is: b) Bauxite.
Andhra Pradesh is one of the leading producers of bauxite in India. The state has significant deposits of bauxite, which is a mineral used to produce aluminum. The bauxite deposits are located in the districts of Kurnool, Kadapa, and Anantapur.
Limestone is a sedimentary rock composed of calcium carbonate. It is used in a variety of industries, including construction, cement, and steel. Andhra Pradesh has significant deposits of limestone, but it is not the state’s most important mineral.
Iron ore is a mineral that is used to produce iron. It is found in rocks and minerals, and it is the primary raw material used in the production of steel. Andhra Pradesh has some iron ore deposits, but they are not as significant as the bauxite deposits.
Coal is a fossil fuel that is used to generate electricity and produce steel. Andhra Pradesh has some coal deposits, but they are not as significant as the bauxite deposits.