Biological Oxygen Demand (BOD) is a standard criterion for? Pollution assay in aquatic ecosystems? Assessing oxygen levels in high altitude regions? [2017]

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

Explanation

Option (c) is correct

Water pollution by organic wastes is measured in terms of Biochemical Oxygen Demand (BOD).
BOD is the amount of dissolved oxygen needed by bacteria to decompose the organic wastes present in water. It is expressed in milligrams of oxygen per litre of water.
The higher value of BOD indicates high pollution due to biodegradable organic wastes and low DO content of water. Since BOD is limited to biodegradable materials, it is not a reliable method of measuring water pollution.

Table categorizing water quality based on BOD levels in mg/liter, using color-coded ranges: green (1-2) for very good, yellow (3-5) for fair, orange (6-9) for poor, and red (100 or more) for very poor. Each category includes a brief description of pollution level and presence of organic matter or microorganisms.