Which is a non-chemical form of water pollution?

• A. Agricultural chemical runoff
• B. Oil spills
• C. Noise pollution from ships
• D. Thermal pollution

Answer: (C)

Water pollution can be chemical or non-chemical. Non-chemical forms are physical changes or energy inputs rather than new substances entering the water. Noise pollution from ships fits this because it doesn’t add chemicals to the water; it sends underwater sound waves that disrupt aquatic life, interfering with communication, navigation, and behavior. The other options involve introducing chemicals (nutrients or pesticides from agricultural runoff, hydrocarbons from oil spills) or altering a physical property (temperature) without adding substances. So the best non-chemical example here is noise pollution from ships.