All of the following statements about return on investment (ROI) are correct EXCEPT?

a) When used in ROI calculations, turnover equals sales divided by average operating assets.

b) Return on investment (ROI) equals margin multiplied by sales.

c) The use of ROI has a performance measure may lead managers to reject projects that could be favorable to the company as a whole.

d) Using ROI to evaluate performance encourages managers to reduce the investment in operating assets as well as increase net operating income.