Which statement is NOT a recognized category of insecticides?

Which statement is NOT a recognized category of insecticides?

• A. Systemic poisons
• B. Stomach poisons
• C. Contact poisons
• D. Fumigants

Answer: (A)

At play here is how insecticides are categorized by how the pest encounters the chemical. The main groups defined are stomach poisons (insecticides that must be ingested), contact poisons (kill on contact), and fumigants (kill as a gas). Systemic is a descriptor of how the chemical moves within a plant or animal and reaches pests that feed on treated material, not a separate exposure-based category. Because the exam frames categories by exposure route, systemic poisons aren’t listed as a distinct category. That’s why the statement about systemic poisons is the one that isn’t recognized in this context. The other categories directly describe how the insect encounters the product: ingestion, contact, or inhalation.

At play here is how insecticides are categorized by how the pest encounters the chemical. The main groups defined are stomach poisons (insecticides that must be ingested), contact poisons (kill on contact), and fumigants (kill as a gas). Systemic is a descriptor of how the chemical moves within a plant or animal and reaches pests that feed on treated material, not a separate exposure-based category. Because the exam frames categories by exposure route, systemic poisons aren’t listed as a distinct category. That’s why the statement about systemic poisons is the one that isn’t recognized in this context. The other categories directly describe how the insect encounters the product: ingestion, contact, or inhalation.