Rosa deposits $100 in a bank account that pays an annual interest rate of 20 percent. A year later, after Rosa has accumulated $20 in interest, she withdraws her $120. Rosa's purchasing power
A. did not change if the inflation rate was 20 percent.
B. decreased if the inflation rate was -5 percent.
C. increased if the inflation rate was 22 percent.
D. More than one of the above is correct.