Which of the following statements is CORRECT?

a) Other things held constant, the more debt a firm uses, the higher its operating margin will be.

b) Debt management ratios show the extent to which a firm's managers are attempting to magnify returns on owners' capital through the use of financial leverage.

c) Other things held constant, the more debt a firm uses, and the higher its profit margin will be. Other things held constant, the higher a firm's debt ratio, and the higher its TIE ratio will be.

d) Debt management ratios show the extent to which a firm's managers are attempting to reduce risk through the use of financial leverage.

e) The higher the debt ratio, the lower the risk