Name three common parts of a lawn irrigation system and their primary function.

• A. Controller (scheduling), valves (zone control), sprinklers/emitters (water delivery)
• B. Controller (scheduling), pipes (pressure control), sprinklers/emitters (water delivery)
• C. Backflow preventer protects the potable water supply
• D. Controller (scheduling), valves (zone control), backflow preventer (protects potable water supply)

Answer: (A)

Understanding how a lawn irrigation system is organized helps you see why these three parts are the most essential. The controller handles scheduling, telling the system when to start watering and for how long, and it can adjust timing based on weather or user settings. Valves provide zone control, allowing the system to open or close the flow to specific areas of the lawn so you can water different sections independently. Sprinklers or emitters are the water delivery components, applying water to the lawn from above (sprinklers) or at the root zone (emitters) as directed by the controller and valves.

Pipes and fittings move water through the system, but they’re the plumbing that supports delivery rather than the key functional roles highlighted by this question. A backflow preventer protects the potable water supply, which is important for safety, but it’s a protective component rather than a primary operational part involved in scheduling, zone management, and water application.