Final answer:
An example of expansionary fiscal policy is a decrease in taxes, aimed at increasing aggregate demand to counteract a recession.
Step-by-step explanation:
An example of an expansionary fiscal policy is B. A decrease in taxes. This type of policy aims to increase aggregate demand and stimulate economic growth, particularly in times of recession. It does so by increasing consumers' disposable income, thereby boosting consumer spending and driving economic activity. On the other hand, A. A decrease in government spending, C. An increase in investment spending (which is usually induced by monetary policy or the private sector), and D. An increase in the money supply (an example of monetary policy), do not represent fiscal policies.
During a recession, expansionary fiscal policy would most likely involve either reducing tax rates to raise disposable income or increasing government expenditures to stimulate demand directly.