Tilaiya dam was the first of the four multi-purpose dams included in the first phase of Damodar Valley Project. It was constructed across the

The correct answer is: C. Barakar river

Tilaiya Dam is a concrete gravity dam on the Barakar River in the Indian state of Jharkhand. It is the first of the four multi-purpose dams included in the first phase of Damodar Valley Project. The dam was constructed between 1953 and 1963 and is operated by Damodar Valley Corporation.

The dam is 261 meters (856 ft) long and 67 meters (220 ft) high. It has a gross storage capacity of 1,200 million cubic meters (42 billion cubic feet) and a live storage capacity of 800 million cubic meters (28 billion cubic feet). The dam generates 100 MW of hydroelectric power.

The dam has been criticized for its environmental impact. The reservoir has submerged large areas of forest and agricultural land. The dam has also caused the displacement of thousands of people.

The other three dams included in the first phase of Damodar Valley Project are:

• Maithon Dam on the Maithon River
• Panchet Dam on the Barakar River
• Damodar Dam on the Damodar River