NITI Aayog is a policy Think Tank of the Government of India. It replaced:

Correct option is D

The correct answer is (d) Planning Commission of India.

Information Booster:

• NITI Aayog (abbreviation for National Institution for Transforming India) was established in 2015 to replace the Planning Commission which followed a top-down model.
• It is a policy think tank of the Government of India, established with the aim to achieve sustainable development goals with cooperative federalism by fostering the involvement of State Governments of India in the economic policy-making process using a bottom-up approach.