5. In a Stackelberg oligopoly, A. each firm chooses simultaneously and non-cooperatively how much to produce to maximize its own profit. B. each firm chooses simultaneously and non-cooperatively its own product's price to maximize its own profit. C. one firm acts as a quantity leader, choosing its quantity first, while all other firms act as followers, choosing their quantities second and in reaction to the leader. D. each firm makes its profit-maximizing decision while considering the entire market demand, the same as a monopolist