Choose the incorrect sentence regarding $BOD$.

• A
  The amount of dissolved oxygen in water increases, the $BOD$ increases.
• B
  It is possible to estimate the amount of biodegradable organic matter in sewage water by measuring biochemical oxygen demand $(BOD)$.
• C
  Micro-organisms involved in biodegradation of organic matter in the receiving water body consume a lot of oxygen and as a result there is a sharp decline in dissolved oxygen downstream from the point of sewage discharge.
• D
  Decline in dissolved oxygen in water causes mortality of fish and other aquatic creatures.