What do economies of scale, the ownership of essential raw materials, and patents have in common?

A) They must all be present before price discrimination can be practiced.
B) They are all barriers to entry.
C) They all help explain why a monopolist's demand and marginal revenue curves coincide.
D) They all help explain why the long-run average cost curve is U-shaped.

Economies of Scale

Financial advantages that firms enjoy as a result of the size of their operations, causing the per-unit expenditure to typically reduce as the operation's scale increases.

Barriers to Entry

Factors that prevent or hinder new competitors from easily entering into an industry or market, including high startup costs, stringent regulations, or strong brand loyalty among consumers.