In 1950 the average household income was $3,300.In 2000 the average household income was $42,000.To make a valid comparison, we should

Group of answer choices

a)do nothing. We can directly compare the purchasing power of the two figures without doing anything.

b)se real GDP to inflate the 1950 amount.

c) None of the above

d) use a price index to inflate the 1950 amount.