Once Economists Take into Consideration Changes in the Expected Inflation

Multiple Choice

Once economists take into consideration changes in the expected inflation rate and supply shocks,the Phillips curve

A) only remains useful when explaining the long-run trade-off between unemployment and inflation.
B) remains a useful tool for explaining the short-run trade-off between unemployment and inflation.
C) is no longer a useful tool for explaining any trade-off between unemployment and inflation.
D) accurately explains the short-run and long-run trade-offs between unemployment and inflation.