Considering a Plot of the Inflation Rate and the Unemployment

Considering a plot of the inflation rate and the unemployment rate,one might conjecture that the short run Phillips curve was further to the right in the first part of the 2000s than it was in the last part of the 1990s and 2000.

A) If so, this might be the result of a negative supply shock or an increase in expected inflation.
B) Is so, this might be the result of a negative supply shock, or a decrease in expected inflation.
C) If so, this might have been the result of a positive supply shock, or an increase in expected inflation.
D) If so, this might have been the result of a positive supply shock, or a decrease in expected inflation.