A firm has a capital structure of 60% common stock, 5% preferred stock, and 35 percent debt. The dividend payout ratio is 30 percent, the companys equity beta is 1.21, and the tax rate is 25 percent. Given this, which one of the following statement is correct? A) The after-tax cost of debt is greater than the current yield to maturity on the companys outstanding bonds. B) The companys cost of preferred stock is less than the companys actual cost of debt. C) The cost of equity is not affected by a change in the companys tax rate. D) The weighted average cost of capital will remain constant as long as the companys capital structure remains constant.