Respuesta :
Starting a business isn't always easy because of the high starting up cost and other expenses that should be carried out to compete with other businesses.Oligopolies maintain their position of dominance in a market might because it is too costly or difficult for potential rivals to enter the market. These are obstacles that stop or prevent the entrance of a firm in a specific market
The answer is: A) Costs of starting a competing business are too high.
When the cost of starting a competing business is too high, the existing businesses that currently had the largest market share would work together to influence the price by their own. By doing this, they can keep the price of their products relatively high without having to compete with one another. This would enable oligopoly to form within the market.