19. Taking into account the upward-sloping short-run aggregate supply curve, the short-run effect of an increase in government expenditure on real GDP is that
(A)real GDP increases by more in the short run than in the long run.
(B) real GDP increases by the same amount in the short run as in the long run.
(C)real GDP increases by less in the short run than in the long run.
(D)real GDP does not change in the short run because the price level increases.