The correct answer is C. Rohtas.
The Durgavati Major Irrigation Project is a major irrigation project in the state of Bihar, India. It is located on the Son River in the Rohtas district. The project was started in 1972 and completed in 1986. It has a total installed capacity of 1,000 MW and irrigates an area of 1.2 million hectares.
The project consists of a dam, a power plant, and a canal system. The dam is located on the Son River, about 10 km from the town of Rohtas. The power plant is located at the base of the dam. The canal system consists of a main canal and a number of branch canals. The main canal is about 100 km long and the branch canals are about 500 km long.
The project has been a major success in terms of irrigation and power generation. It has also helped to improve the socio-economic conditions of the people in the region.
The other options are incorrect because:
- Gaya is a city in the state of Bihar, India. It is located on the banks of the Falgu River. Gaya is an important religious and cultural center.
- Munger is a city in the state of Bihar, India. It is located on the banks of the Ganges River. Munger is an important educational and commercial center.
- Begusarai is a city in the state of Bihar, India. It is located on the banks of the Ganges River. Begusarai is an important industrial and agricultural center.