Which option lists all three insecticide categories?

Which option lists all three insecticide categories?

• A. Stomach poisons, contact poisons, and fumigants
• B. Stomach poisons
• C. Contact poisons
• D. Fumigants

Answer: (A)

Insecticides are grouped by how the insect encounters and is affected by them: stomach poisons must be ingested, contact poisons kill on direct contact with the insect’s body, and fumigants act as vapors inhaled by the insect. The option that lists all three—stomach poisons, contact poisons, and fumigants—provides the complete set of the major categories you’re expected to know. Stomach poisons are taken in with food and can have systemic effects, contact poisons act quickly on the exterior of the insect, and fumigants diffuse as gases that can reach insects in hidden spaces. The other choices name only one category at a time, so they don’t represent all three.

Insecticides are grouped by how the insect encounters and is affected by them: stomach poisons must be ingested, contact poisons kill on direct contact with the insect’s body, and fumigants act as vapors inhaled by the insect. The option that lists all three—stomach poisons, contact poisons, and fumigants—provides the complete set of the major categories you’re expected to know. Stomach poisons are taken in with food and can have systemic effects, contact poisons act quickly on the exterior of the insect, and fumigants diffuse as gases that can reach insects in hidden spaces. The other choices name only one category at a time, so they don’t represent all three.