Final answer:
An economist who believes in monetarism would most likely say that C. the supply of money is what impacts an economy the most.
Step-by-step explanation:
Monetarism is an economic theory associated with economist Milton Friedman. It emphasizes the role of money supply in influencing economic outcomes, advocating for stable and predictable growth in the money supply to control inflation. Monetarists argue that central banks should focus on managing the money supply to achieve macroeconomic stability.
An economist who believes in monetarism would most likely say that the supply of money is what impacts an economy the most. Monetarism theory emphasizes that the control of money in circulation is crucial. It argues that changes in the money supply, such as printing more money, can lead to inflation and other economic variations.