Which of the following best describes a multiple-user water supply system?

The best description of a multiple-user water supply system is that it is a nonpublic water supply system for human consumption. This type of system is capable of serving multiple users, such as households or communities, as opposed to being restricted to a single user or purpose.

In the context of water supply systems, a nonpublic supply indicates that the system is not governed by the same regulations as public water supplies, which are required to meet stricter health and safety standards due to the need to ensure safe drinking water for larger populations. The focus on human consumption highlights the primary function of these systems, which is to provide safe and adequate water for people to use.

While the other options touch on specific aspects of water supply systems, they do not encapsulate the essence of a multiple-user system as effectively. Private use is too restrictive, industrial purposes are specific to a particular type of consumer and not necessarily indicative of multiple users, and stating there are no limits on population served is too vague and can imply a misrepresentation of the system's capacity and regulation. Therefore, the characterization as a nonpublic water supply for human consumption accurately reflects the intended use and operational scope of a multiple-user water supply system.