Which statement best describes biological control?

• A. Biological control relies on naturally occurring disease organisms, parasites, or predators to control pests
• B. Biological control uses synthetic chemicals to control pests
• C. Biological control uses mechanical barriers
• D. Biological control relies on genetic modification

Answer: (A)

Biological control means using living organisms—such as pathogens, parasites, or predators—that naturally limit pest populations. This approach relies on ecological relationships to keep pests in check rather than relying on chemicals, physical barriers, or genetic modification. For example, introducing parasitic wasps to attack caterpillars or using Bacillus thuringiensis, a microbial agent that harms specific insect larvae, are classic examples. Because it uses living antagonists to reduce pests, it’s distinct from synthetic pesticides (chemicals), mechanical barriers (physical blocks), or genetic modification (engineered traits). Therefore, relying on naturally occurring disease organisms, parasites, or predators to control pests best captures this concept.