Suppose that irrational exuberance has generated an increase in investment spending so that the current level of output exceeds the long-run natural level. If policymakers choose to engage in activist stabilization policy, they should

a. decrease government spending, which shifts aggregate demand to the left
b. decrease government spending, which shifts aggregate demand to the right
Oc. decrease taxes, which shifts aggregate demand to the right
d. decrease taxes, which shifts aggregate demand to the left