The Relationship Between the Long-Run Total Cost Curve and the Marginal

The relationship between the long-run total cost curve and the marginal and average cost curves is best described by which of the following statements?

A) The slope of the total cost curve from the origin to a point on the total cost curve is how you derive the marginal cost curve while the average cost is given by TC/Q.
B) Marginal cost is MC/Q while average cost is TC/Q.
C) Marginal cost is derived by dividing total cost by a constant as is average cost.
D) The slope of the total cost curve at each point is how you derive the marginal cost curve while the slope from the origin to a point on the total cost curve is how you derive the average cost curve.