An increase in planned real investment spending causes
A) a movement along the C + I + G + X curve and a shift of the aggregate demand curve.
B) a shift of the C + I + G + X curve and a movement along the aggregate demand curve.
C) a shift of the C + I + G + X curve but has no effect on the aggregate demand curve.
D) a shift of the C + I + G + X curve that causes the aggregate demand curve to shift.
Answer: D