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Organic matter is considered as a major ...

Organic matter is considered as a major source of water pollution caused by wastes of food , animal and human excreta, garbage etc. the excess of organic matter in water causd a threat to aquatic life because

A

the space available to acquatic life decreases

B

microorganisms consume dissolved oxygen to decompose organic matter

C

organic matter is swallowed by small animals

D

decomposition of organic matter increases the temperature of water .

Text Solution

Verified by Experts

The correct Answer is:
B
If a lot of organic matter is decomposed , a lot of dissolved oxygen is consumed by microorganisms hence dissolved oxygen is no longer available for aquatic life .
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