The Before-Tax Cost of Debt, Rd, Is the Same as The

The before-tax cost of debt, rd, is the same as the:

A) yield to maturity (YTM) associated with the firm's bonds.
B) dividend yield associated with the firm's common stock.
C) average coupon rate on the firm's bonds.
D) return on equity if the firm has no preferred stock.
E) the firm's marginal tax rate.