The correct answer is Koyna. Explanation & Key Takeaways: • India has the world's fifth-largest hydropower capacity and is home to several large hydroelectric power plants generating clean, renewable electricity. • Koyna Hydroelectric Project – • Located near Patan, in Maharashtra’s Satara district, close to the Koyna River, the Koyna Hydroelectric Project is Maharashtra’s largest completed hydroelectric power plant with a capacity of 1,960MW. Hence, option 2 is correct. • Owned and operated by MAHAGENCO and Maharashtra State Power Generation, the Koyna Project has four dams, the largest of which is constructed across the Koyna River. • As the dam is located in the Western Ghats mountain range, all the generators of the power plant have been installed deep inside the mountains requiring extensive excavation works. • The construction began in 1954, and the project has been developed in four stages. • Vaitarana Hydro Power Project- • It is a 60MW hydropower project. • It is located on the Vaitarana river/basin in Maharashtra, India. • The project is currently active. It has been developed in a single phase. • Post completion of construction, the project got commissioned in 1976. • Khopoli Hydro Power Project • It is erected in the Khopoli town of Raigad district in the state of Maharashtra in India. • The power project is commissioned in 1915. • The main reservoir of the power project is Walwhan Lake. • This hydroelectric project is owned by Tata Power.