Which of the following is true about an over-fertile lake?

In an over-fertile, eutrophic lake the quality of the fish produced is impaired.

Heavy nutrient loading drives algal blooms whose decay strips oxygen from the water.

Nitrate levels rise rather than fall as nutrients accumulate.

Algal productivity surges rather than declines, forming thick blooms.

Oxygen levels drop rather than rise as decaying algae consume dissolved oxygen.

The resulting low-oxygen water favours coarse, low-value fish over quality species.