Which of the following is NOT a function of Reserve Bank of India?

Manages Credit Rating of Banks
The Reserve Bank of India (RBI) was established on April 1, 1935 in accordance with the provisions of the Reserve Bank of India Act, 1934. The main functions of RBI: RBI controls the credit operations of banks through quantitative and qualitative tools, holds the cash reserves of all the scheduled banks, controls the banking system through the system of licensing, inspection and calling for information, acts as the lender of the last resort by providing rediscount facilities to scheduled banks, has sole right to issue bank notes of all denominations etc.