Which of the Following Statements Is False

Which of the following statements is false?

A) The marginal cost of the fifth unit of output equals the total cost of five units minus the total cost of four units.
B) The total variable cost of seven units equals the average variable cost of seven units times seven.
C) If marginal cost is rising, then average variable cost must be rising.
D) The marginal cost of the fifth unit of output equals the total variable cost of five units minus the total variable cost of four units.