Which of the following statements best describe the Modigliani and Miller's proposition 2?

a. None of the other statements is correct.

b. Even if we assume that the cost of debt increases with the debt to equity ratio, the weighted average cost of capital will stay constant.

c. More than one of the other statements is correct.

d. The cost of equity will stay constant regardless of the firm's debt to equity ratio. e. Since the cost of debt is usually lower than the cost of equity, adding leverage to the firm will lower the weighted average cost of capital.