Which statement is true of a productively efficient firm in a perfectly competitive industry? In long-run equilibrium under conditions of perfect competition and productive efficiency, all firms produce at minimum:Multiple Choiceaverage total cost.total cost.marginal cost.average variable cost. Which statement is true of a productively efficient firm in a perfectly competitive industry? In long-run equilibrium under conditions of perfect competition and productive efficiency, all firms produce at minimum:

a) Average total cost.
b) Total cost.
c) Marginal cost.
d) Average variable cost.