Which of the following statements is correct? a. The more similar Firm A's product is to Firm B's product, the more likely Firm A is to advertise. b. Monopolistically competitive firms advertise in order to increase the elasticity of the demand curve they face. c. Brand names may help consumers if they provide information about the quality of a product when acquiring such information is difficult. d. According to the signaling theory, the more product information an advertisement contains the more effective it is