The correct answer is: Kaimur.
Kaimur district is the largest district in Bihar, India, with an area of 3,295 square kilometers (1,270 sq mi). It is located in the southern part of the state, and is bordered by the districts of Rohtas to the north, Aurangabad to the east, Gaya to the southeast, Jharkhand to the south, and West Champaran to the west. The district headquarters is at Bhabua.
Kaimur district is a hilly region, and is part of the Kaimur Range. The main rivers in the district are the Son, the Ganges, and the Ghaghara. The district is also home to a number of forests, including the Kaimur National Park.
The population of Kaimur district is 2,326,637 (2011 census). The majority of the population is Hindu, followed by Muslims and Christians. The main languages spoken in the district are Hindi and Bhojpuri.
The economy of Kaimur district is based on agriculture, forestry, and mining. The main crops grown in the district are rice, wheat, maize, and sugarcane. The district is also home to a number of mines, including coal mines and iron ore mines.
Kaimur district is a beautiful and scenic region, with a rich history and culture. The district is home to a number of historical monuments, including the ruins of the ancient city of Rajgir. The district is also home to a number of temples and mosques.
Kaimur district is a great place to visit for those who are interested in history, culture, and nature. The district has a lot to offer visitors, including beautiful scenery, historical monuments, and temples and mosques.