The correct answer is C. Raipur.
Raipur is the capital of the Indian state of Chhattisgarh. It is the largest city in the state and the headquarters of Raipur district. The city is located on the banks of the Mahanadi River.
Raipur is a major industrial and commercial center. The city is home to a number of industries, including steel, cement, and power. Raipur is also a major transportation hub. The city is connected to other parts of the country by road, rail, and air.
Limestone is a sedimentary rock composed mainly of calcium carbonate. It is a major source of calcium and is used in a variety of industries, including construction, cement, and steel.
Limestone is found in abundance in Raipur district. The district is home to a number of limestone mines. The limestone produced in Raipur district is of high quality and is exported to a number of countries.
The other options are incorrect because they are not districts in Chhattisgarh.