In 1970,Professor Plum Earned $12,000;in 1980,he Earned $24,000;and in 1990,he

Multiple Choice

In 1970,Professor Plum earned $12,000;in 1980,he earned $24,000;and in 1990,he earned $36,000.If the CPI was 40 in 1970,70 in 1980,and 130 in 1990,then in real terms,Professor Plum's salary was highest in

A) 1970 and lowest in 1980.
B) 1970 and lowest in 1990.
C) 1980 and lowest in 1970.
D) 1980 and lowest in 1990.