The primary objective of using indirect instruments of monetary policy is to control inflation by influencing the cost and availability of money and credit in the economy.

All of the options listed are indirect instruments of monetary policy. Open market operations involve the buying and selling of government securities by the central bank, reserve requirements are the amount of reserves that banks are required to hold, and the discount rate is the interest rate charged by the central bank to banks for loans.

Open market operations influence the cost and availability of money and credit by increasing or decreasing the supply of money in the economy, changing the interest rates charged by banks, and affecting the demand for money and credit.

Increasing reserve requirements increases the amount of reserves that banks are required to hold, which reduces the amount of money that they have available to lend. This leads to an increase in the cost and availability of money and credit.

Increasing the discount rate increases the interest rate that banks pay to borrow money from the central bank. This leads to an increase in the cost of money for banks, which is passed on to borrowers in the form of higher interest rates on loans.

Moral suasion is a non-binding request or suggestion made by the central bank to banks and other financial institutions to encourage or discourage certain types of lending or investment. It is not an indirect instrument of monetary policy because it does not involve the use of economic tools to influence the cost and availability of money and credit.

Quantitative easing involves the central bank buying large quantities of government securities and other financial assets from banks and other financial institutions. This increases the money supply and reduces interest rates, which leads to a decrease in the cost and availability of money and credit.

Selective credit controls involve the central bank imposing restrictions on the amount of credit that banks can lend to specific sectors or activities. This leads to an increase in the cost and availability of money and credit for those sectors or activities.

Open market operations are not a type of selective credit control because they do not involve the central bank imposing restrictions on the amount of credit that banks can lend to specific sectors or activities.

Margin requirements involve the central bank requiring investors to put up a certain amount of their own money when buying certain types of assets, such as stocks or bonds. This increases the cost and availability of money and credit for those sectors or activities.

Credit rationing involves banks limiting the amount of credit that they are willing to lend to specific sectors or activities. This leads to an increase in the cost and availability of money and credit for those sectors or activities.

Margin requirements are an example of a selective credit control because they involve the central bank requiring investors to put up a certain amount of their own money when buying certain types of assets, such as stocks or bonds.

Open market operations involve the central bank buying and selling government securities. When the central bank buys government securities, it increases the money supply and reduces interest rates, which leads to a decrease in the cost and availability of money and credit.

The discount rate is the interest rate that the central bank charges banks for loans. When the central bank increases the discount rate, it becomes more expensive for banks to borrow money, which leads to an increase in the cost and availability of money and credit.

Moral suasion is not an indirect instrument of monetary policy because it does not involve the use of economic tools to influence the cost and availability of money and credit.