Step 1: Recall the Nagarjunasagar project.
The Nagarjunasagar dam is one of the largest masonry dams in the world. It was built for irrigation, hydroelectric power generation, and water supply purposes.
Step 2: Identify the river.
The project is situated in Andhra Pradesh and Telangana on the Krishna River. It provides irrigation to a large command area and is a landmark multipurpose river valley project in India.
Step 3: Eliminate other rivers.
- Godavari River is the site of projects like Polavaram and Jayakwadi, not Nagarjunasagar.
- Pennar River has smaller irrigation projects, but not Nagarjunasagar.
- Mahanadi River has the Hirakud Dam, not Nagarjunasagar.
Step 4: Conclusion.
Therefore, Nagarjunasagar project was established on the Krishna River.
Final Answer: \[ \boxed{\text{Nagarjunasagar project is on the Krishna River.}} \]
Fill in the blank with the correct option.
The teacher believed that the student’s sudden lack of interest in class was an ..........., as he had always been enthusiastic and attentive.