Explanation:

- Option 1: S Ramakrishnan - There's no known appointment of S Ramakrishnan as Chief Economic Advisor. This option is likely incorrect.

- Option 2: Krishnamurthy Subramanian - He served as the Chief Economic Advisor before 2022. He completed his term before the current appointment.

- Option 3: Raghuram Rajan - Known as a former Reserve Bank of India Governor, he was never a Chief Economic Advisor during the specified time.

- Option 4: V Anantha Nageswaran - He was appointed as the Chief Economic Advisor to the Government of India in January 2022. His education and experience in economics led to his selection.