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When huge amount of sewage is dumped int...

When huge amount of sewage is dumped into a river, its BOD will

A

increase

B

decrease

C

sharply decrease

D

remain unchanged

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Verified by Experts

The correct Answer is:
A
Degree of impurity of water due to organic matter is measured in terms of BOD (`O_(2)` in milligram required for five days in one litre of `H_(2)O` at `20^(@)C` for micro-organisms to metabolise organic wastes).
In polluted water reoxygenation decreases than deoxygenation. So, in this water BOD (Biological Oxygen Demand) increases.
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