The production possibilities curve:
a. shows all of those levels of production that are consistent with a stable price level.
b. indicates that any combination of goods lying outside the curve is economically inefficient.
c. is a frontier between all combinations of two goods that can be produced and those combinations that cannot be produced.
d. shows all of those combinations of two goods that are most preferred by society.

The correct answer is option C.

Explanation:

The production possibility frontier shows the maximum possible bundles or combinations of two goods that can be produced using the given resources completely.  

All the points on and below the frontier are attainable. The points above the frontier are unattainable as they need more resources.  

The points below the frontier though attainable are inefficient, this is because all the resources are not being used.  

So we can say that the production possibility curve is a frontier between a combination of two goods that are attainable and that are not attainable.

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