The model of the kinked demand curve in price competition implies that:

a. free entry in the market will eventually reduce economic profits to zero.
b. firms will coordinate prices so as to maximize group profit.
c. strong brand loyalty by consumers gives firms little incentive to reduce prices.
d. a firm's competitors will match any price cuts by the firm but not price hikes.
e. firms in the market match the market price set by a single dominant firm.