Answer: Option A
Explanation:
The fertilizers that is being supplied into the plants contains huge amount of nitrogen and phosphorus in it. The extra fertilizers from the ground move to the nearby local water bodies.
These nutrients n water serves as the food for the algal and make them grow at higher growth rate.
They start consuming the oxygen in water and thus affecting the other aquatic animals found in water.
Because of this reason there is a disturbance in the equilibrium of ecosystem as if the aquatic animals will die there will be a decrease in the population of animals feeding on aquatic animals.