Which of the Following Is True About the Keynesian Aggregate

Multiple Choice

Which of the following is true about the Keynesian aggregate supply (AS) curve?

A) The short-run AS is flat,but the long-run AS is vertical.
B) The short-run AS is upward sloping but the long-run AS is flat.
C) The short-run AS is upward sloping but the long-run AS is vertical.
D) The short-run and the long-run AS are upward sloping.