If a firm's net sales (i.e., revenue) decreases, but total assets, its debt ratio, and its net profit margin remain the same as they were before net sales decreased, the firm's:

a. ROE would not change.

b. ROE could either increase or decrease depending on the interaction between the equity multiplier and the days payable ratio.

c. ROE would increase.

d. ROE would decrease.

e. There is insufficient information to determine the effect on ROE.