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Which of the following statement(s) is/are an INCORRECT reason for eutrophication? (A) excessive use of fertilisers (B) excessive use of detergents (C) dense plant population in water bodies (D) lack of nutrients in water bodies that prevents plant growth Choose the most appropriate answer:

1. (A) only
2. (C) only
3. (B) and (D) only
4. (D) only

Correct answer: (D) only

Solution

Eutrophication is over-enrichment of water with nutrients (from fertilisers, detergents) causing excessive plant/algae growth; therefore (D), which says lack of nutrients prevents plant growth, is the only incorrect reason.

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