According to the source, do market structures such as monopoly, monopolistic competition, and oligopoly generally achieve the same productive and allocative efficiency as perfect competition?

1. Perfect competition is described as a hypothetical benchmark against which other market structures can be compared. 2. In monopoly, monopolistic competition, and oligopoly, firms will not always produce at minimum average cost or set price equal to marginal cost. 3. Because those two conditions are not met, these market structures will not produce productive and allocative efficiency. 4. This is a direct comparison the source draws, not a claim that efficiency cannot be compared across structures. _Source: OpenStax Principles of Microeconomics for AP Courses (CC BY 4.0), Ch 8 "Perfect Competition", section 8.4 | Efficiency in Perfectly Competitive Markets_