What do BOD and COD measure in water quality assessment, and what does a higher value indicate?

What do BOD and COD measure in water quality assessment, and what does a higher value indicate?

• A. BOD measures chemical oxygen demand; COD measures biological oxygen demand; higher values indicate less pollution.
• B. BOD measures biodegradable organic matter; COD measures chemical oxidizable organics; higher values indicate greater pollution and potential oxygen depletion.
• C. BOD measures total dissolved solids; COD measures turbidity.
• D. BOD and COD both measure oxygen generation in water.

Answer: (B)