A firm has a net profit/pretax profit ratio of .6, a leverage ratio of 1.5, a pretax profit/EBIT of .7, an asset turnover ratio of 4, a current ratio of 2, and a return-on-sales ratio of 6%. Its ROE is _________.

A. 15.12%
B. 20.16%
C. 30.24%
D. 7.56%