Long-Run Marginal Cost Is

Multiple Choice

Long-run marginal cost is:

A) the derivative of the short-run total cost function with respect to Q.
B) the derivative of the long-run total cost function with respect to Q.
C) derived by plugging the firm's long-run input demands into the long-run total cost function.
D) derived by plugging the firm's short-run input demands into the long-run total cost function.