Final answer:
The correct answer is option C. Oligopoly and monopoly.
Step-by-step explanation:
Large barriers to entry are characteristic of certain market structures, specifically oligopoly and monopoly. In a monopolistic market, there is only one producer with a unique product, leading to very high barriers to entry. This singular dominance over the market can be due to patents, government regulations, or high startup costs that prevent other firms from entering the market.
On the other hand, an oligopoly is a market dominated by a few firms, such as the commercial aircraft industry which is mainly controlled by Boeing and Airbus, or the soft drink industry dominated by Coca-Cola and Pepsi. These few firms face high barriers to entry due to factors like economies of scale, strategic behavior, and governmental barriers which can discourage new competitors.
On the contrary, perfect competition and monopolistic competition have lower barriers to entry. In perfectly competitive markets, there are many firms selling identical products, and there are no barriers to entry or exit. Monopolistic competition features a larger number of firms compared to oligopoly, and while they sell differentiated products, the barriers to entry are still relatively low compared to monopoly and oligopoly.