The Following Figure Shows the Production Possibilities Frontier for Good

The following figure shows the production possibilities frontier for Good A and Good B.In the figure below,point f represents: Figure 2.2

A) an efficient combination of Good A and Good B.
B) the only efficient combination of Good A and Good B.
C) the combination of Good A and Good B that the economy will produce.
D) an inefficient combination of Good A and Good B.
E) the only inefficient combination of Good A and Good B.