The correct answer is Minimum reserve ratio. The minimum reserve ratio is sometimes used as a tool in monetary policy, influencing the country's borrowing and interest rates by changing the number of funds available for banks to make loans with. Liquid assets to be maintained are in the form of cash, gold, and unencumbered approved securities as per section 24 of the Banking Regulation Act, 1949. Reserve Bank of India under the RBI Act, Section 22 is solely accountable for the issuance of currency notes excluding rupee one-note issued by the Finance Secretary of the Government of India. RBI controls the circulation of the banknotes in the country primarily to generate confidence among citizens of genuineness, quality, and credibility of currency issued besides bringing in uniformity in the issuance of notes. Due to the presence of only one authority, there is an effective control on the flow of credit in and out of the market.