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The Venn diagram shows the relationships between different market structures and their associated concepts. Perfect competition has identical products, no advantage, demand equal to marginal revenue, and both efficiencies. Monopolistic competition has differentiated products, excess advertising, more elastic demand than monopoly, and price equals average total cost. Oligopoly has identical products, no advantage, demand greater than marginal revenue, and price makes a profit. Monopoly has a unique good, price discrimination, high barriers to entry, and ability to make long-run profits with inefficiency. The diagram highlights differences between the market structures and shows that some concepts may overlap between them.