The highest body that approves Five-Year Plans in India is the National Development Council. Let`s dissect each option to better understand why option 2 is the correct answer.
Option 1: Planning Commission - The Planning Commission was the body responsible for formulating and overseeing the implementation of Five-Year Plans in India until it was abolished in 2014. However, it was not the highest body that approved the plans.
Option 2: National Development Council - The National Development Council (NDC) is the highest body that approves Five-Year Plans in India. It is a forum that includes the Prime Minister, Chief Ministers of all states, and members from various ministries and departments. The NDC reviews the draft plans prepared by the Planning Commission and provides approval.
Option 3: Interstate Council - The Interstate Council is a constitutional body in India that aims to promote coordination and cooperation among states. While it plays an important role in inter-state relations, it is not directly involved in approving Five-Year Plans.
Option 4: Union Cabinet - The Union Cabinet comprises ministers responsible for various government departments and is the main decision-making body of the central government. While the Union Cabinet may discuss and provide inputs on Five-Year Plans, it does not have the authority to approve them.
Therefore, the correct answer