At its profit-maximizing output,a pure nondiscriminating monopolist achieves:

A) neither productive efficiency nor allocative efficiency.
B) both productive efficiency and allocative efficiency.
C) productive efficiency but not allocative efficiency.
D) allocative efficiency but not productive efficiency.

A pure nondiscriminating monopolist achieves neither productive efficiency nor allocative efficiency because it restricts output to a level where marginal revenue (MR) equals marginal cost (MC), which results in a higher price and lower quantity than the socially optimal level. This lack of allocative efficiency means that some consumers who are willing to pay more for the product cannot purchase it, while some who are willing to pay less for the product do purchase it. Additionally, the monopolist does not achieve productive efficiency, which is the production of output at the lowest possible cost, because it has no incentive to operate at the minimum point of its average total cost curve.