Which of the following best describes a key feature of fiscal policy?

The key feature of fiscal policy is its role in influencing the economy through government spending and taxation. Fiscal policy involves the decisions made by the government regarding its expenditures and the revenue it generates, primarily through taxes. By adjusting these two levers, the government can impact overall economic activity. For example, increasing government spending can stimulate economic growth, especially during a recession, by providing more capital to businesses and individuals, thereby increasing demand. Conversely, changing tax rates can influence consumers' disposable income and investment decisions, further impacting economic performance.

The other options do not accurately represent the primary function of fiscal policy. While regulating trade balances involves international economic considerations, it is more closely related to trade policy or monetary policy. Focusing exclusively on the money supply pertains to monetary policy, which is managed by central banks rather than fiscal policymakers. Enforcing price controls on goods falls under regulatory measures and economic interventions that are not inherently related to fiscal policy, which is primarily concerned with budgetary measures.