Final answer:
Barriers to entry in a market are conditions that prevent or discourage new competitors from entering, such as economies of scale, control of resources, legal restrictions, and intellectual property protections.
Step-by-step explanation:
Barriers to entry include elements that prevent or discourage competitors from entering the market. Some common barriers are economies of scale that can lead to a natural monopoly, control of a physical resource, legal restrictions on competition, and various forms of intellectual property protection, such as patents, copyrights, trademarks, and trade secrets. Additionally, there might be practices aimed to intimidate the competition, such as predatory pricing. A natural monopoly is a situation where the economies of scale are so significant that if one firm supplies the entire market, it becomes impractical for new firms to enter due to inherent cost disadvantages.
Of the options provided to the student, the correct answer would be (3) prevention of new competitors from entering the market, as it is the essence of what constitutes barriers to entry in an economic context.