这道题目不需要用到effective tax rate的公式吗

问题如下：

At the beginning of 2013, company M issued 5-year bonds with the face value of $2,000,000. The market interest rate is 7%, every 31 December the bonds will pay 6% coupon. At the beginning of 2014, the market interest rate changes to 8%. In the given situation, the effective interest rate is:

选项：

A.

6%.

B.

7%.

C.

8%

解释：

B is correct. Based on definition, the effective interest rate is the market interest rate when bond is issued.