Final answer:
Coca-Cola's monopoly in the soft drink market is largely due to economies of scale and brand loyalty, which serve as significant barriers to new competitors.
Step-by-step explanation:
Monopolies are known to exist largely due to various kinds of barriers to entry, which can prevent or discourage potential competitors from entering a market and challenging existing firms. When it comes to Coca-Cola's vast market share in the soft drink market, several barriers to entry might apply, but the predominant ones are likely economies of scale and brand loyalty.
Coca-Cola benefits from significant economies of scale, meaning it can produce at a lower average cost due to its large scale of operation. Additionally, Coca-Cola has built up considerable brand loyalty over the years, making it difficult for new entrants to compete against the established brand association and consumer preferences enjoyed by Coca-Cola.