The correct answer is: a) Bauxite and manganese.
Bauxite is an ore that is the main source of aluminum. It is a reddish-brown ore that is found in tropical and subtropical regions. Manganese is a metal that is used in a variety of products, including batteries, steel, and alloys. It is a black ore that is found in many parts of the world.
The Eastern Ghats region of Andhra Pradesh is rich in bauxite and manganese. The bauxite is found in the hills of the Eastern Ghats, and the manganese is found in the plains. The bauxite is mined and processed to produce aluminum, and the manganese is mined and processed to produce manganese metal.
The other options are incorrect. Limestone is a sedimentary rock that is composed of calcium carbonate. It is used in a variety of products, including cement, concrete, and fertilizer. Coal is a fossil fuel that is used to generate electricity. Iron ore is a mineral that is used to produce iron. Uranium is a radioactive metal that is used to produce nuclear energy. Gold and diamonds are precious metals and stones that are found in a variety of locations around the world.