The correct answer is option 'C' - duopoly.

Explanation:

Duopoly is a type of market structure in which there are only two buyers facing a large number of sellers. In this market system, the two buyers have a significant influence on the market as they have the power to determine the prices and quantities of goods or services purchased.

In a duopoly, the two buyers compete with each other to obtain the best deals from the sellers. The sellers, on the other hand, compete with each other to attract the attention of the buyers and secure their business. This competition among sellers can lead to lower prices and better quality products or services.

Duopolies can arise in various industries, such as telecommunications, airlines, and automobile manufacturing. For example, in the telecommunications industry, there may be only two major players who dominate the market and compete for customers. These two buyers have the ability to negotiate better deals with the sellers, who are numerous and compete with each other to secure contracts with the buyers.

In a duopoly market, the buyers have a significant amount of market power as they can dictate the terms of trade to the sellers. This can result in an imbalance of power, as the sellers may have limited options and may be forced to accept lower prices or unfavorable terms.

Overall, a duopoly market system consists of two buyers facing a large number of sellers. The buyers have significant market power and can influence the prices and quantities of goods or services purchased. This market structure can lead to intense competition among sellers and potentially benefit consumers through lower prices and improved quality.