Concept: Points inside or within a Production Possibilities Curve show underutilisation of available resources.
Explanation: The PPC shows the maximum possible output an economy can produce using all resources efficiently.
Points on the curve represent efficient production, where resources are fully used.
Points outside the curve are unattainable with current resources and technology.
Points within the curve are attainable because the economy can produce less than the maximum.
However, they indicate inefficiency, as resources are not fully or efficiently used.
Answer: B. attainable but inefficient production levels.