A spraying device that uses a grooved spinning cup to break the spray stream into uniform droplets and applies low gallons per acre is:

• A. Fogger
• B. Boom sprayer
• C. Controlled Droplet Applicator (CDA)
• D. Rotating disc

Answer: (C)

Controlling droplet size while using low gallons per acre is the key idea here. A grooved spinning cup atomizes the spray by centrifugal action, breaking the stream into droplets that are uniform in size. This kind of controlled, uniform droplet production at low application rates is what a Controlled Droplet Applicator is designed to do. Foggers produce very fine droplets with a high drift risk and are not suited for precise low-volume deposition. Boom sprayers deliver larger volumes and are not focused on achieving uniform small droplets at low GPA. A rotating disc describes a mechanism used in some atomizers, but the description—with the grooved cup producing uniform droplets at low gallons per acre—best fits the Controlled Droplet Applicator.