The Keynesian cross model of an economy with an equilibrium level of income, E, is shown at right. Suppose the price level changes and the aggrgegate expenditure line shifts to C + 1 + G + X' In this case, the price level O A. is unchanged and there will be a movement downward along the aggregate demand curve (not shown) O B. has fallen and there will be a movement upward along the aggregate demand curve (not shown) O C. has fallen and there will be a movement downward along the aggregate demand curve (not shown). O D. has risen and there will be a movement upward along the aggregate demand curve (not shown)