请问这题考的是哪一个知识点？

问题如下：

(1) The best answer to Paul’s first question is to use the:

选项：

company’s overall cost of capital.

company’s before-tax cost of debt.

yield on high-quality corporate bonds.

解释：

C is correct. The yield on high-quality corporate bonds in the appropriate discount rate used to calculate the present value of the future benefits represents the rate at which the defined benefit obligation could be effectively settled.