Which hazard category is known to cause cancer or be presumed carcinogenic to humans?

• A. Reproductive Toxicants
• B. Eye Hazards
• C. Mutagens
• D. Carcinogens

Answer: (D)

Carcinogens are substances known to cause cancer in humans or animals, or believed to cause cancer based on the available evidence. The wording “known to cause cancer or be presumed carcinogenic to humans” matches this category exactly, making it the best fit. Reproductive toxicants affect fertility or development, not cancer risk. Eye hazards deal with damage to the eyes. Mutagens cause genetic mutations and can contribute to cancer, but mutagenicity is a separate hazard class; the explicit cancer-causing risk is captured by the carcinogens category. For example, benzene is a well-known carcinogen.