well there was a land bridge so the answer is b
land bridge is what i found.
Monopoly
Oligopoly
Purely competitive market
The correct answer is: "Perfectly competitive market".
A purely competitive or perfect competition market is characterized by the participation of a large number of both sellers and buyers. In such a situation, each producer receives a very small share of the total market, therefore it lacks the power to influence on its conditions. Individual producers have zero influence on prices, this is why they are denominated price-takers.
Consumers are the ones who set the prices through their actions within the markets, that in turn determine the intersection of demand and total supply. They will able to acquire the products they are demanding at better market prices.