Which statement regarding cost of capital is true? a. Because no flotation costs are required to obtain capital as retained earnings, the cost of retained earnings is generally lower than the after-tax cost of debt. b. Higher flotation costs tend to reduce the cost of equity capital. c. Because of the risk of bankruptcy, the cost of debt is always higher than the cost of equity capital. d. If a company assigns the same cost of capital to all of its projects regardless of each projects risk, then the company is likely to reject some safe projects that it should accept and to accept some risky projects that it should reject.