The correct answer is (b), Santhanam Committee.
The Santhanam Committee was set up in 1964 to review the working of the administrative machinery of the Government of India. The Committee made a number of recommendations for improving the efficiency and effectiveness of the administration. However, it did not make any recommendations on the Panchayati Raj System.
The Ashok Mehta Committee was set up in 1977 to review the working of the Panchayati Raj System. The Committee made a number of recommendations for strengthening the Panchayati Raj System. These recommendations were accepted by the Government of India and implemented.
The V.K.R.V. Rao Committee was set up in 1985 to review the working of the rural development programmes. The Committee made a number of recommendations for improving the effectiveness of the rural development programmes. These recommendations were accepted by the Government of India and implemented.
The Balwant Rai Mehta Committee was set up in 1957 to study the working of the Panchayati Raj System in Rajasthan. The Committee made a number of recommendations for strengthening the Panchayati Raj System. These recommendations were accepted by the Government of India and implemented in all the states of India.