Which of the following is/are helpful for evaluating the effect of leverage on a company's risk and potential returns?

I. Estimated pro forma coverage ratios

II. The recognition that financing decisions do not affect firm or shareholder value

III. A range of earnings chart and proximity of expected EBIT to the breakeven value

IV. A conservative debt policy that obviates the need to evaluate risk

a. I only b. III only c. I and III only d. II and III only e. IV only