The correct answer is A (Oligopoly). In an oligopoly, a small number of firms dominate the market, leading to interdependence among them. Each firm must anticipate and react to the pricing and production strategies of its competitors. For example, commercial airlines often adjust their pricing and route schedules based on the expected actions of rival carriers. This dynamic is less prevalent in B (Perfect competition), where numerous firms act as price takers, or C (Monopolistic competition), where product differentiation drives pricing power rather than competitor reactions.