According to a Theory That Relies on the Rational Expectations

According to a theory that relies on the rational expectations hypothesis and the assumption that wages and prices are flexible, why do anticipated expansionary monetary actions NOT boost real GDP?

A) Anticipated expansionary monetary policy actions do not increase aggregate demand.
B) The short-run aggregate supply curve shifts upward simultaneously with the rightward shift of aggregate demand.
C) The short-run aggregate supply curve shifts downward simultaneously with the upward shift of aggregate demand.
D) The higher interest rates associated with anticipated expansionary monetary policy actions will dampen investment spending.