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JEE Advanced levelOne or more correct optionsDifficulty 3 of 3ev156

Select the correct statements about eutrophication.

APhosphate builders in detergents can contribute to it
BIt lowers the BOD of the lake because algae release oxygen
CNitrate and phosphate in run-off encourage excessive growth of algae
DDecomposition of dead algae by aerobic bacteria lowers the dissolved oxygen

Answer: A, C, D

Nutrient enrichment causes algal blooms. When the algae die, aerobic decomposition consumes oxygen and the BOD rises, so the claim that BOD falls is false. Phosphate from detergents is one source of nutrients.

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