The stock of Vuong Properties has a beta of .86. The risk-free rate of return is 3.1 percent, the inflation rate is 2.2 percent, and the expected market rate of return is 13.75 percent. What is the equity risk premium on Vuong's stock?
A. 12.9%
B. 9.2%
C. 12.4%
D. 10.7%