Which piping type supplies a number of smaller areas within a supply network?

The correct choice is distribution mains. In a fire protection system, distribution mains are specifically designed to carry water from the main supply lines to various points within a building or facility. They branch off to supply water to smaller areas where fire protection systems, such as sprinklers or standpipes, are located. This network of distribution mains is crucial for ensuring that adequate water pressure and flow are available when needed in case of a fire emergency.

Main supply lines, while also important, primarily transport water from a source or reservoir to the distribution system but do not typically supply the smaller areas directly. Service piping generally connects the water service from the distribution system to buildings, and while feeder lines deliver water to specific locations, they usually feed from the distribution mains rather than directly supplying smaller areas.