Which of the following is not a barrier to entry?

A) patents
B) X-inefficiency
C) economies of scale
D) ownership of essential resources

Barriers to Entry

Obstacles that make it difficult for new firms to enter a market, such as high startup costs or stringent regulations.

X-inefficiency

The production of output, whatever its level, at a higher average (and total) cost than is necessary for producing that level of output.