Prostuti360°Prostuti360°
Log in

WBCS Main Examination 2023 — Paper IV: General Studies II · Question 47 of 200

Q47
General ScienceEnvironment & Ecology
BOD increases in a waterbody due to the increase of
  1. a.Phytoplankton
  2. b.Zooplankton
  3. c.Sewage
  4. d.Heavy Metals

Answer: (C) Sewage

Biochemical oxygen demand measures how much oxygen microbes need to decompose organic matter, so adding organic sewage raises BOD sharply. Heavy metals are toxic but not biodegradable organic load, and plankton are not the main driver named here.

Q46 Whole paperQ48
BOD increases in a waterbody due to the increase of — WBCS Main Examination 2023 Q47 | Prostuti360°