An eutrophic lake

1.Is rich in nutrients

2.Is poor in organic matter

3.Has high algal blooms

4.Is rich in dissolved oxygen

5.Has no issue with the survival of fish and other aquatic life

A1, 2 & 3 only

B3, 4 & 5 only

C1 & 3 only ✓ Correct

D2 & 4 only

Correct answer: (C) 1 & 3 only

Explanation

A eutrophic lake is enriched with nutrients like nitrogen and phosphorus.

Statement 1: this nutrient richness is the defining feature of eutrophication.

Statement 3: the excess nutrients fuel heavy algal blooms on the surface.

Statement 2: such a lake is rich, not poor, in organic matter, so it is wrong.

Statement 4 and Statement 5: decaying algae strip dissolved oxygen and threaten fish, so those are wrong.

Advanced eutrophication can turn a lake into an oxygen-starved dead zone.

Want more like this? Create a free account to practise a full test, track your progress, and get spaced-repetition review.