Q. Biological Oxygen Demand (BOD) is a standard criterion for

• Measuring oxygen levels in blood
• Computing- oxygen levels in forest ecosystems
• Pollution assay in aquatic ecosystems
• Assessing oxygen levels in high altitude regions

Answer: (c) Pollution assay in aquatic ecosystems

Notes:

Biological Oxygen Demand (BOD):

• It is the amount of dissolved oxygen needed by aerobic biological organisms to break down organic material present in a given water sample at a certain temperature over a specific time period to break down organic material present in that water.
• BOD is often used in wastewater-treatment plants and is used as an index of the degree of organic pollution in water.