Which liquid pesticide formulation may contain close to 100% active ingredient?

The correct choice is ultra low volume (ULV) pesticide formulations. ULV formulations are designed to deliver a high concentration of active ingredient with minimal carrier volume. This allows for effective treatment of pests while minimizing the amount of liquid needed for application. Due to their formulation, ULV products can often contain close to 100% active ingredients, which is advantageous in terms of both cost-effectiveness and environmental impact.

In contrast, other formulations typically contain a greater percentage of inert ingredients or solvents that dilute the active substance. For instance, ready-to-use solutions are primarily designed for convenience and are typically diluted for consumer use, which keeps the active ingredient concentration lower. Emulsifiable concentrates and suspension concentrates also involve significant amounts of solvents or carriers to facilitate application and stability, thus containing less than 100% active ingredient.