Q. Firms like Papa John's Pizza Hut as well as Domino's sell pizza and other products that are differentiated in nature. While numerous pizza chains exist in most locations differentiated nature of these firms' products permits them to charge prices above marginal price. Given these observations, is the pizza industry most likely monopolistically competitive and a monopoly, perfectly competitive also an oligopoly industry? Use the causal view of structure, conduct, and performance to elucidate the role of differentiation in the market for pizza. Then apply the feedback critique to the role of differentiation in the industry.