(Answered) (exhibit: markets and efficiency) in a panel (a)(exhibit: markets and efficiency) in a panel (a)

➤ Why might panel (a) indicate an efficient market outcome?
Panel (a) indicates efficiency when the market clears at the point where marginal benefit equals marginal cost. At that point, total surplus is maximized and no additional mutually beneficial trades remain. The result assumes no externalities, public goods, or significant transaction costs, which would otherwise alter the efficient allocation shown.