How is a pesticide defined?

• A. A substance designed to control living organisms such as plants or animals.
• B. A chemical used to improve crop color.
• C. A fertilizer that enhances growth.
• D. A tool used to spray water.

Answer: (A)

A pesticide is a substance or mixture that is used to prevent, destroy, repel, or control pests—living organisms such as weeds, insects, fungi, or other animals that affect crops or stored products. This definition focuses on the purpose: managing organisms that are pests, not on cosmetic improvements or general growth. The option describing a substance intended to control living organisms best captures this idea. The other options describe things that aren’t about pest management: improving crop color, boosting growth with a fertilizer, or a tool for spraying water.