Correct Option
Statement 1: The National Ganga River Basin Authority (NGRBA) adopted a river basin as the unit for planning and management. This approach facilitates integrated water resources management by considering the entire river system, including its tributaries and catchment area, holistically.
Statement 2: The NGRBA was constituted under the Environment (Protection) Act, 1986, as an apex body at the national level. Its mandate was to spearhead, plan, finance, monitor, and coordinate the conservation and pollution abatement efforts for the Ganga River.
Incorrect Options
Statement 3: The Prime Minister of India was the ex-officio Chairman of the NGRBA. While Chief Ministers of the states through which the Ganga flows were members of the Authority, the chairmanship was not held by them on a rotational basis. Therefore, statement 3 is incorrect.
Options (B), (C), and (D) are incorrect as they include statement 3, which is factually inaccurate.