Which term describes a biological or chemical substance or situation dangerous to humans and the environment?

• A. Hypotension
• B. Poison
• C. Tachypnea
• D. Biohazard

Answer: (D)

A biohazard refers to a biological or environmental threat that can harm people or ecosystems. It covers materials and situations involving infectious agents, contaminated waste, body fluids, cultures, or any biological material that could spread disease. That makes it the best fit for describing something dangerous to humans and the environment in a health-care or lab setting, because it signals the specific type of hazard: biological. The other options are individual clinical signs or substances that don’t describe the hazard category. Hypotension and tachypnea are physiological states, not hazard labels. Poison usually denotes a toxic chemical substance, not a biological or environmental hazard. In practice, recognizing a biohazard guides proper precautions, labeling, and disposal to protect workers and the environment.