Brand loyalty is associated with

a. monopoly, because having no alternatives, consumers eventually become loyal to the goods the monopolist produces.

b. monopolistic competition, because monopolistically competitive firms advertise to create a stronger loyalty to their goods.

c. monopolistic competition, because not producing differentiated products, monopolistically competitive firms must find a way to create a loyalty to their goods.

d. perfect competition, because perfectly competitive firms cannot influence price, so they compete by creating brand loyalty.

e. monopoly, oligopoly, monopolistic competition, and perfect competition, because all firms want to increase their market share, so each engages in creating brand loyalty.