Figure 3.3.1 -Which Statement About the PPF in Figure 3.3.1 Is True

Figure 3.3.1
-Which statement about the PPF in Figure 3.3.1 is true?

A) Inputs are equally productive in all activities.
B) Points inside the frontier represent impossible combinations of good X and good Y.
C) The opportunity cost of producing good X decreases as production of X increases.
D) The opportunity cost of producing good Y increases as production of Y increases.
E) Changes in consumer preferences for good X or good Y will shift the PPF.