The correct answer is: d) All of the above.
The Nagarjuna Sagar Dam is a multi-purpose dam on the Krishna River in the Indian state of Andhra Pradesh. It was constructed between 1955 and 1969 and is the second largest dam in India by volume. The dam has a number of purposes, including irrigation, hydroelectric power generation, flood control, and navigation.
The dam has been instrumental in the development of agriculture in Andhra Pradesh. It provides irrigation water to over 1.2 million hectares of land, which has helped to increase crop yields and improve the livelihoods of farmers. The dam also generates hydroelectric power, which is used to meet the electricity needs of the state.
The dam has also been effective in controlling floods. It has reduced the frequency and severity of floods in the Krishna River basin, which has saved lives and property. The dam also helps to improve navigation on the Krishna River, which is important for the transportation of goods and people.
Overall, the construction of the Nagarjuna Sagar Dam has had a positive impact on the development of Andhra Pradesh. It has helped to improve agriculture, generate electricity, control floods, and improve navigation.