When every good or service is produced up to the point where the last unit provides a marginal benefit to society equal to the marginal cost of producing it, occurs.

Allocative efficiency

Explanation:

Marginal benefit refers to the extra satisfaction derived from purchase of an extra unit of a good or a service.

Marginal cost refers to the extra cost incurred when an additional unit of a good or a service is produced.

When marginal cost is equal to the marginal benefit, it is the most efficient situation wherein optimal blend of commodities is produced.

Allocative efficiency refers to producers providing that blend of goods which are most desired by the society at the optimal level of production.

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