The answer is c. Oligopoly
A monopoly exists when a single company dominates the entire market for a particular product or service. Since the interviewee mentions two companies, Apple and Samsung, this option is not applicable.
Pure competition is a market structure characterized by a large number of small firms, none of which can control the market price. This does not fit the scenario described, as only two companies are mentioned.
An oligopoly is a market structure where a small number of firms have significant market power and dominate the market. The statement that Apple and Samsung are the only two companies really selling smartphones suggests that they are the dominant players in the market, fitting the definition of an oligopoly.
Socialistic competition is not a recognized market structure in economic theory. Therefore, this option is not relevant.
Monopolistic competition is a market structure where many firms sell products that are similar but not identical. Given that the interviewee highlights only two dominant companies, this option does not apply.
Therefore, the most appropriate competitive structure for Apple and Samsung in this context is an oligopoly.