In-line eductor is defined as:

• A. A device used to inject foam into water near nozzle.
• B. Eductor that is placed along the length of a hoseline; most common type.
• C. A device that measures foam concentrate quantity.
• D. The finished foam after aeration.

Answer: (B)

An inline eductor is a foam proportioning device that uses the Venturi effect to draw foam concentrate into the water as it flows through the hose line. It is installed along the length of the hoseline, which is why it’s described as the most common type—the foam concentrate is mixed into the water directly in the line before it reaches the nozzle, giving consistent foam production with the flow.

This matches the described function of being placed along the length of the hoseline. The other options describe devices or outcomes that aren’t about drawing concentrate into the water within the hose line: injecting foam near the nozzle is a different arrangement, a device that measures concentrate is a metering tool, and finished foam after aeration is the end product, not the eductor itself.