In the Context of the Calculation of the Net Income

In the context of the calculation of the net income of a firm, the final step of the process comprises:

A) finding the firm's accounts receivable for goods sold on credit.
B) finding the difference between the firm's gross profit and its operating expenses.
C) deducting the firm's interest expenses and taxes from its net operating income.
D) deducting the firm's costs of goods sold from its revenue.