The Below Figure Shows the Various Combinations of the Goods

The below figure shows the various combinations of the goods X and Y that yield different levels of utility.Figure 7.3

-If the average variable cost of a firm is falling, then the:

A) average fixed cost must be rising.
B) marginal cost must be falling.
C) marginal cost must be rising.
D) marginal cost lies below the average variable cost.
E) marginal cost lies above the average variable cost.