The correct answer is Bastar.
Bastar is the largest district in Chhattisgarh by area. It is located in the southern part of the state and has a population of over 2.2 million people. The district is known for its dense forests, tribal culture, and mineral resources.
Raigarh is the second largest district in Chhattisgarh. It is located in the central part of the state and has a population of over 1.7 million people. The district is known for its coal mines, iron ore mines, and steel plants.
Surguja is the third largest district in Chhattisgarh. It is located in the northern part of the state and has a population of over 1.5 million people. The district is known for its forests, wildlife, and tribal culture.
Koriya is the fourth largest district in Chhattisgarh. It is located in the eastern part of the state and has a population of over 1.3 million people. The district is known for its coal mines, iron ore mines, and steel plants.