What type of pesticide formulation would typically contain a large amount of inert carrier with a small amount of active ingredient?

The correct choice highlights a formulation that is characterized by a high proportion of inert materials relative to the active ingredient. Dust formulations usually consist of finely ground particles with a low concentration of active ingredients mixed with inert carriers. This structure allows for easy application, particularly in areas where a fine distribution of the product is necessary.

When considering other formulation types, dry flowables contain active ingredients that have been formulated to dissolve or disperse in water, but they typically have a greater active ingredient concentration compared to dusts. Emulsifiable concentrates combine active ingredients with oils or solvents for dilution in water, also featuring higher active levels. Liquid concentrates have an even higher active ingredient concentration, making them more potent than dust formulations.

Thus, dusts stand out due to their unique composition and low active ingredient ratio, designed for specific applications where extensive coverage is required without overwhelming the target area with the active ingredient.