Hydro Systems has 15-year bonds outstanding with a coupon rate of 6 percent. Interest is paid annually. The face amount of each bond is $1,000. What is the company's pre-tax cost of debt if the bonds currently sell for $1,080?
A) 5.22 percent
B) 5.55 percent
C) 4.71 percent
D) 5.36 percent
E) 4.42 percent