The Figure Given Below Shows the Aggregate Demand and Supply

Multiple Choice

The figure given below shows the aggregate demand and supply curves of a perfectly competitive market.Figure 10.7

-In which of the following situations, is a barrier to entry into a monopoly least likely to exist?

A) A large firm enjoys economies of scale.
B) The tariffs on foreign goods are eliminated by the government.
C) A company is the sole inventor of what it produces and no one else can make a good substitute.
D) Government restrictions such as license requirements are enacted.
E) A company is the only owner of an essential resource needed to produce its product.