Which of the Following Statements Is True of the U

Which of the following statements is true of the U.S. experience with regards to the Phillips curve hypothesis?
I. Values of inflation and unemployment rates during the 1960s generally conformed to the tradeoff implied by the Phillips curve.
II. Annual observations of inflation and unemployment from 1961 to 2015 do not
Seem consistent with a Phillips curve.
III. Annual observations of inflation and unemployment from 1961 to 2015 seem consistent
With a Phillips curve.

A) I only
B) II only
C) I and II only
D) III only