Economic efficiency in a competitive market is achieved when

when you operate with your own products

Explanation:

economically doing well on business and people loving the pricws

The correct answer is letter "A": the marginal benefit equals the marginal cost from the last unit sold.

Explanation:

Economic efficiency is achieved if resources are distributed optimally to reduce waste and best serve each person in that economy. In economic technical terms, there will be the same level of marginal benefit and marginal cost. When Economic Efficiency exists, the cost of manufactured goods is the lowest possible and any change would affect any given consumer in the market.