Final answer:
In monopolistic competition, the entry of new firms is the most difficult compared to other industry structures.
Step-by-step explanation:
In monopolistic competition, the entry of new firms is the most difficult compared to other industry structures. Monopolistic competition is a market structure in which many firms compete by producing differentiated products that are close substitutes for one another. Since each firm has a unique product and uses product differentiation to attract customers, it creates barriers for new firms trying to enter the market.