The Combined Efforts of the Fed and the Treasury in Response

The combined efforts of the Fed and the Treasury in response to the financial crisis following the housing market crash caused:

A) the aggregate supply curve to shift to the right, back to its pre-crisis level.
B) the aggregate supply curve to shift to the left, far below its pre-crisis level.
C) the aggregate demand curve to shift to the right, back to its pre-crisis level.
D) the aggregate supply curve to shift to the left, back to its pre-crisis level.