Which of the Following Is True of Marginal Revenue

Which of the following is true of marginal revenue?

A) Marginal revenue equals total revenue divided by quantity.
B) Marginal revenue is the slope of the supply curve of a firm.
C) Marginal revenue is the slope of the total cost curve when profit is maximized.
D) Marginal revenue equals the change in total revenue divided by the change in the quantity.
E) Marginal revenue equals the income earned by selling the stocks on the margin.