Answer:
The correct option is C) An industry that runs best when one firm produces all the output.
Step-by-step explanation:
A monopoly is when the entire output is achieved through just one seller. Therefore it is characterized by a lack of competition among sellers in an economic reference in order to produce any good or service.
This can lead to a monopoly of high pricing on these products and services which is set on a high profit margin thus making the seller high monopoly profits.