Correct Option
The Inter-State Council is established as per the provisions of the Constitution of India. Article 263 of the Constitution empowers the President to constitute such a body if it appears that the public interest would be served by its establishment. The Council's primary role is to inquire into and advise upon disputes between states, investigate and discuss subjects of common interest between the Union and states or among states, and make recommendations for better coordination of policy and action. It was formally established in 1990 following the recommendations of the Sarkaria Commission.
Incorrect Options
The National Security Council is not a constitutional body. It was established in 1998 by an executive order of the Government of India to advise the Prime Minister on matters of national security and strategic interest.
Zonal Councils are also not constitutional bodies. They were established under the States Reorganisation Act, 1956, which is an Act of Parliament. These are statutory bodies created to foster inter-state cooperation in various fields such as economic and social planning, border disputes, and transport. There are five Zonal Councils: Northern, Central, Eastern, Western, and Southern. The Union Home Minister serves as their Chairman.