Final answer:
Used motor oil, antifreeze, and oil filters should be recycled and kept out of the water supply to prevent contamination and protect aquatic life and human health.
Step-by-step explanation:
Used motor oil, antifreeze, and oil filters should be recycled to keep them out of the water supply. When these substances are not properly disposed of, they can contaminate water sources and pose a threat to aquatic life and human health. Substances like polycyclic aromatic hydrocarbon (PAH) found in crude oil and trichloroethylene (TCE) found in antifreeze can be harmful if consumed or absorbed by fish and wildlife, which can then be consumed by humans.