Which of the Following Defines Spontaneously Generated Funds

Which of the following defines spontaneously generated funds?

A) the amount of assets required per dollar of sales
B) a forecasting approach in which the forecasted percentage of sales for each item is held constant
C) funds that a firm must raise externally through borrowing or by selling new common or preferred stock
D) funds that are obtained automatically from normal operations, and they include spontaneous increases in accounts payable and accruals, plus additions to retained earnings