Which of the following pesticide formulations must be mixed with water before being used by the applicator?

The choice of flowables as the formulation that must be mixed with water before use is accurate because flowable formulations are designed to be diluted in water prior to application. These formulations consist of finely ground solid particles suspended in a liquid, which allows them to be easily mixed with water for effective application. The mixing process helps to ensure that the active ingredient is evenly distributed in the solution, facilitating proper delivery onto the target area.

In contrast, granulars are typically applied directly to the soil or vegetation without needing any additional mixing with water. Emulsifiable concentrates also require mixing with water, but they form a stable emulsion rather than just being suspended particles, which makes them somewhat different in behavior compared to flowables. Baits are generally used as is, often in a ready-to-use format, and they do not necessitate mixing with water for application. Hence, flowables are specifically characterized by their requirement for water mixing, making this answer spot on for the question posed.