The net operating profit margin is 19% for WidgetCo and 21% for Tool. Which of the following statements is the most plausible explanation of the difference in observed net operating profit margins?
WidgetCo's has lower financial leverage.
WidgetCo uses LIFO and Tools uses FIFO.
WidgetCo's has a lower tax rate.
WidgetCo's net operating asset turnover.