Answer : 3. "Jawaharlal Nehru "
Explanation :

The statement "Dams are the temples of modern India" is often attributed to Jawaharlal Nehru, the first Prime Minister of India. Nehru used this expression to highlight the significance of multi-purpose river valley projects, particularly dams, in the development and progress of the country. These projects were seen as essential for irrigation, hydroelectric power generation, and overall economic development.