<prompt> Biological oxidation demand is determined bySullageSuspended SolidsAlgae in waterOrganic matter  <response>: D Organic matter Biochemical oxygen demand BOD is the amount of oxygen absorbed by a sample of sewage during a specified period at a specified temperature for the aerobic destruction or use of organic matter by living organisms. BOD 300 mgL is strong sewage; BOD 100 mgL is weak sewage. It is due to organic matter present in the sewage. 