Concept:Central banks use treasury bills as a monetary policy tool to control the money supply in the economy.
Explanation:When the central bank sells treasury bills to the public, buyers pay using cash from their bank accounts or savings.
This removes money from the economy and reduces the total cash held by individuals and businesses.
As a result, the amount of cash in circulation decreases, which helps to control inflation and stabilise the economy.
The central bank is not trying to increase cash in the banking system, raise revenue for commercial banks, or earn profits for private investors.
Its main purpose is to absorb excess liquidity from the market.
Answer:D. reduce cash in circulation