Interest Rates in the United States Have

Interest rates in the United States have

A) held remarkably steady over the past two decades.
B) shown some variability over the past two decades but less in the early 1980s than the mid-1960s.
C) shown significant variability over the past two decades, with no discernible correlation with movement in GDP.
D) tended to peak just when the economy is turning out of a recession and into a period of prolonged recovery.
E) none of the above.