Which Definition Is INCORRECT

Which definition is INCORRECT?

A) Biochemical oxygen demand (BOD) -the amount of O2 required for the microbial decomposition of organic matter in a sample.
B) Indicator organisms-microbes whose presence in an environment suggests fecal contamination.
C) Primary treatment-a wastewater treatment process that uses microbes to convert suspended solids to inorganic compounds and removable cell mass.
D) Constructed wetland-method of wastewater treatment in which water is channeled into ponds where aerobic and anaerobic degradation occurs.
E) Anaerobic digestion-process that uses anaerobic microbes to degrade the sludge obtained during wastewater treatment.