Final answer:
The incorrect statement is that 'producers of smartphones gain' in a transition from a monopoly to a perfectly competitive market. While society, total surplus, and consumers gain with reduced deadweight loss, producers might not gain due to increased competition and lower prices.
Step-by-step explanation:
When comparing a perfectly competitive market to a monopoly in the context of the smartphone industry, several economic outcomes can be observed. In a perfectly competitive market, society usually gains because consumer surplus and producer surplus typically increase, leading to a higher total surplus. This economic transition also often results in the elimination of deadweight loss, which is a loss of economic efficiency in terms of potential gains not realized by consumers or producers. However, one incorrect statement among the options provided is that 'producers of smartphones gain' (Choice D). In a monopoly, the producer can set higher prices and earn greater profits due to a lack of competition. By contrast, in a perfectly competitive market, the increased competition generally leads to lower prices and profits for individual firms, thereby potentially reducing the gains for smartphone producers. Therefore, while consumers of smartphones and society as a whole may benefit from increased efficiency and lower prices, producers may not necessarily gain in a perfectly competitive market.