The correct answer is: A. advertise its product on television.
In a perfectly competitive market, there are many firms selling identical products. This means that each firm has a very small share of the market and has no control over the market price. As a result, firms in a perfectly competitive market must compete on price. They can do this by advertising their products, offering discounts, or lowering their prices.
Option B is incorrect because firms in a perfectly competitive market have easy access to information about the market price. This is because there are many firms selling identical products, so the price is easy to observe.
Option C is incorrect because firms in a perfectly competitive market cannot settle for whatever price is offered. This is because they have no control over the market price. If they try to charge a higher price, consumers will simply buy from one of the many other firms selling identical products.
Option D is incorrect because firms in a perfectly competitive market have a very difficult time keeping other firms out of the market. This is because there are no barriers to entry in a perfectly competitive market. Any firm can enter the market and sell identical products.
In conclusion, the correct answer is: A. advertise its product on television.