Final answer:
Sony producing games for both the PlayStation 4 and Nintendo Wii U represents platform diversification, where Sony expands its market reach to include users of another console.
Step-by-step explanation:
When Sony starts producing games for both its PlayStation 4 and the Nintendo Wii U, it is engaging in a business strategy known as platform diversification. This strategy involves expanding the company's product offerings to include additional gaming platforms beyond its own. By doing so, Sony would be capitalizing on the market presence of different consoles, potentially increasing its revenue by tapping into the customer base of the Nintendo Wii U. Since its introduction in 2006, the Wii has revolutionized the gaming industry by encouraging players to use their bodies to interact with games, which could offer Sony new avenues for game development.