21. According to the compromise theory (by DeAngelo and Masulis), which of the following is true? a. Firms with stable and large future taxable income ought to borrow less. b. Firms with other tax saving means should borrow more. c. As the debt ratio increases, value of a firm increases initially but decreases later. d. Value of a firm is independent of capital structure. e. Firms should use debt as much as possible