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O-LevelBiologyEcology & Environment5090/11 · May/June 2025 · Q391 Mark

Untreated sewage contains nitrates and phosphates. What will happen in the lake if untreated sewage is added?

Aincreased biodiversity
Bincreased eutrophication
Cincreased fish populations
Dincreased light penetration

✓ Correct answer

B: increased eutrophication

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About this question

Topic
Ecology & Environment, O-Level Biology (syllabus 5090). Multiple choice, 1 mark.
Source
O-Level Biology, May/June 2025 Paper 1 Variant 1, question 39.

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