A natural monopoly arises whenA. a single firm aggressively forces other competitors to exit and industry. B. a single firm has a monopoly over natural resources. C. two firms merge into a single firm in order to capture more of the market. D. a single firm can produce more cheaply than multiple firms due to a downward-sloping average total cost curve.

D

Explanation:

A monopoly is when there is only one firm operating in an industry. there are usually high barriers to entry of firms. the demand curve is downward sloping. it sets the price for its goods and services.

An example of a monopoly is a utility company

A natural monopoly occurs due to the high start-up costs or a large economies of scale.

Natural monopolies are usually the only company providing a service in a particular region  

Characteristics of natural monopolies

the correct answer option is b. a single paragraph.

explanation:

when you are thinking about paragraph​ topics, you should always choose a subject that can be adequately addressed in a single paragraph.

a paragraph is a piece of writing consisting of a few sentences that deal with a single theme. it has only a single idea that the paragraph revolves around and talks about.

so a paragraph topic must be chosen wisely where a single idea can be communicated in a single paragraph.