An economy is at full-employment equilibrium. if consumers and firms become more optimistic about future income and profits, which of the following will occur in the short run?
a. aggregate demand will shift rightward, increasing real output and decreasing the price level.
b. aggregate demand will shift rightward, decreasing real output and increasing the price level.
c. aggregate demand will shift rightward, increasing real output and the price level.
d. short-run aggregate supply will shift rightward, increasing real output and the price level.
e. short-run aggregate supply will shift rightward, decreasing real output and the price level.