Consider the Long-Run Average Cost Curve for a Firm

Multiple Choice

Consider the long-run average cost curve for a firm.Any point representing a cost and output combination that is below the LRAC curve

A) may represent actual cost and production levels in the short run.
B) represents less efficient cost levels than points on the long-run average cost curve.
C) is attainable only when all factors are variable.
D) represents unattainable cost levels,given current technologies.
E) is attainable if the firm minimizes its costs according to the "principle of substitution."