Question

Eutrophication of water bodies which kills fishes leads to depletion of

• A. Oxygen
• B. Food
• C. Essential minerals
• D. Light

Answer 1

The correct option is A

Oxygen

The correct option is A.

Explanation for correct option:

1. Eutrophication is the process of mineralization of the water body.
2. This process is known to deplete the biochemical oxygen demand (B.O.D.) of the water body leading to killing of fish and other organisms.

Explanation for incorrect options:

Option B:

1. During eutrophication water blooms or high concentrations of algae develop in the water body leading to higher availability of food for other organisms.

Option C:

1. Minerals such as nitrogen and phosphorus increase in water body during eutrophication leading to mineralization.

Option D:

1. In presence of light increase in number of phytoplanktons that synthesize their food by photosynthesis occurs.

Final answer: The level of oxygen depletes during eutrophication leading to killing of fishes.