Answer:
D. A market failure is when the market fails to produce the efficient level of output.
Step-by-step explanation:
A market failure is when the market fails to produce the efficient level of output.
This ultimately implies that, a market failure arises when there is inefficiency in the distribution or allocation of goods and services in a free market. Thus, the demand of the consumer of these goods and services are not being met with the level of supply (output) required i.e the forces of demand and supply are not efficient in producing the level of output required by the economy.
Some of the causes of market failure are imperfect information, monopoly, oligopoly, externalities etc.