What role does equilibrium price play in achieving productive and allocative efficiency in perfectly competitive markets?

• A. Equilibrium price ensures that firms produce at the maximum average total cost.
• B. Equilibrium price ensures that average revenue equals average total cost.
• C. Equilibrium price ensures that marginal cost is greater than marginal benefit.
• D. Equilibrium price ensures that firms produce at the minimum average total cost and that marginal benefit equals marginal cost.

Answer: (D)