Your portfolio has provided you with returns of 8.6 percent, 14.2 percent, -3.7 percent, and 12.0 percent over the past four years, respectively. What is the geometric average return for this period?

A. 7.25 percent

B. 7.54 percent

C. 7.57 percent

D. 7.63 percent

E. 9.55 percent