Final answer:
The control of the money supply by the Federal Reserve System is known as monetary policy.
Step-by-step explanation:
The control of the money supply by the Federal Reserve System is known as monetary policy. Monetary policy refers to the actions undertaken by the US central bank to influence the availability and cost of money and credit in order to promote national economic goals. The Federal Reserve regulates the supply of money in the economy through monetary policy by either expanding or contracting the money supply.