Tarun Bharat Sangh, an organization based in a village near Alwar (Rajasthan), has become famous because of:

Tarun Bharat Sangh is a non governmental organization led by Rajendra Singh, who is widely known as the Waterman of India. The organization gained international recognition for its extensive work in water conservation and environmental restoration in the arid regions of Rajasthan. Since its founding in 1975, the group has focused on reviving traditional Indian methods of water management, specifically through the construction of Johads, which are small earthen check dams. These structures capture rainwater and allow it to percolate into the ground, recharging dry aquifers and bringing seasonal rivers back to life. Because of these successful community based rainwater harvesting initiatives, option D is the correct answer.