The rate of inflation in the United States since 1960 has:

a. remained below 1.3% as a result of effective Federal Reserve monetary policy.
. increased steadily from 1.3% to 14% and then decreased steadily back to 1.3%.
c. declined steadily and predictably from 14% to 1.3%.
d. fluctuated between 1.3 and 14%, often catching many people by surprise.