Which formulation is characterized by active ingredients adhered to the outside of a carrier that needs agitation?

The formulation characterized by active ingredients adhered to the outside of a carrier that requires agitation is known as a wettable powder. This type of formulation consists of finely powdered active ingredients that are not soluble in water but can be suspended when mixed with water. The need for agitation is crucial because it helps to disperse the powder evenly throughout the liquid, ensuring that the active ingredient is effectively delivered during application.

Wettable powders are commonly used for pest control as they can provide a high concentration of active ingredients while being environmentally friendly due to their reduced risk of leaching into groundwater. This formulation can also allow for better coverage of surfaces during application, which can enhance the effectiveness of pest management strategies.

The other options—granules, dust, and fumigants—are characterized by different delivery methods and do not require the same type of agitation. Granules are solid particles that can be spread on surfaces, dusts are fine particles that can be applied directly without agitation, and fumigants are vapors used for treating areas without a need for agitation at all. Understanding the differences among these formulations is essential for selecting the appropriate pest control method in various situations.