What Can Be Concluded from Milton Friedman and Edmund Phelps

Multiple Choice

What can be concluded from Milton Friedman and Edmund Phelps' expectations-augmented Phillips curve?

A) that there is a long run tradeoff between unemployment and inflation
B) that there is a short run tradeoff between unemployment and inflation
C) that inflation is positively related to the unemployment gap
D) all of the above
E) none of the above