Over the last four years, the stock of Wagner's Paints has had an arithmetic average return of 6.5 percent. Three of those four years produced returns of 9 percent, 3 percent, and 1 percent. What is the geometric average return for this 4-year period?

a. 3.00 percent b. 4.48 percent c. 6.33 percent d. 7.07 percent e. 8.69 percent