What type of water system serves temporary visitors at commercial campgrounds?

The identification of a transient non-community water system as the correct answer is based on the nature of its use. These systems are specifically designed to cater to establishments where people do not remain for an extended period, such as commercial campgrounds. Visitors at these campgrounds typically stay temporarily, making a transient non-community water system suitable for their needs.

This type of system differs from a non-transient system, which serves a population that remains at a location for longer periods but does not provide service to the general public in a community. A community water system is built to supply water to a permanent residential population, which is not the case for temporary visitors. Similarly, a private water system, while also for personal use, typically does not cater to the public or transient visitors, but rather serves individual households or properties.

In essence, the transient non-community water system is tailored specifically for the unique needs of temporary visitors, such as those found in campgrounds, making it the most appropriate choice in this scenario.