AAD's outstanding bonds have a 25-year maturity and a $1,000 par value. Their yield to maturity is 9.25%, they pay coupon payments semiannually, and they sell at a price of $850. What is the bonds' (annual) coupon rate? Select one: O a. 7.22% O b. 6.27% O c. 6.60% O d. 7.7% O e. 6.95%