Final answer:
In response to a recessionary gap, the appropriate fiscal policy response would be to reduce taxes or increase government spending. This will shift the aggregate expenditure function up and result in a new equilibrium at potential GDP.
Step-by-step explanation:
The appropriate response to a recessionary gap is for the government to reduce taxes or increase spending so that the aggregate expenditure function shifts up from AEo to AE₁. When this shift occurs, the new equilibrium E₁ now occurs at potential GDP as shown in Figure D9 (a).