Macro Economic Misery Diminished During the First Reagan Administration,which Means

Macro economic misery diminished during the first Reagan administration,which means that the Phillips curve

A) Maintained its position despite important changes in the composition of the labor force.
B) Shifted to the left,thereby implying an easing of the trade-off between inflation and unemployment.
C) Shifted to the right,thereby implying that stagflation had become a more acute problem than before.
D) Flattened out,thereby implying that some amount of inflation is consistent with any rate of unemployment.