Which of the following is included as an accessory?

• A. Filters
• B. Sensors
• C. Regulators
• D. Hoses

Answer: (B)

In irrigation design, an accessory is something that adds capability or automation without being required for water to be delivered to plants. Sensors fit this role because they provide data—such as soil moisture, rainfall, or system pressure—that can trigger the controller to adjust irrigation automatically. This improves efficiency and water savings, even though the system could operate without them. The other items are more integral to the basic delivery and protection of the system: hoses are part of the physical water distribution to zones, regulators keep pressure at a usable level for emitters, and filters protect emitters and valves from debris. While those components are important, they are not added features that enhance smart operation in the same way sensors do.