Arrange the following concepts in the correct sequence that illustrates the transition from market inefficiency to optimal outcomes: A) Identification of deadweight loss, B) Implementation of corrective measures, C) Achievement of allocative efficiency, D) Recognition of externalities.

To illustrate the transition from market inefficiency to optimal outcomes, we start with the recognition of externalities. This means understanding how certain actions by individuals or companies can affect others, like pollution from a factory. Once we recognize these externalities, we can identify the deadweight loss, which occurs when resources are not used efficiently, leading to a loss in overall welfare. After identifying the problem, we can implement corrective measures, such as taxes or regulations, to address these inefficiencies. Finally, with these measures in place, we achieve allocative efficiency, where resources are used in a way that maximizes the overall benefit to society, like ensuring that the costs of pollution are reflected in the price of goods.