During the Period 1984 to 2008,the Average Yield on 3-Month

During the period 1984 to 2008,the average yield on 3-Month U.S.Treasury bills was 4.76%,the average inflation rate was 2.97%,the average yield on 30-year Treasury bonds was 6.89%,and the average return on 30-year Aaa-Rated Corporate Bonds was 7.73%.The real risk-free short-term interest rate is

A) 1.79%.
B) 2.13%.
C) 2.97%.
D) 4.76%.