The fish in a pond are dying because of algal bloom. algal bloom is caused by the presence of excess phosphorus or sulfur in the pond. an investigation into the matter indicates that chemical fertilizers made in a factory nearby are responsible for the presence of these chemicals in water. under what conditions might this data be considered biased? a) if there are no other possible sources of fertilizers near the pond. b) if other living organisms in the pond were also dying along with the fish. c) if the farms nearby use organic fertilizers rather than chemical fertilizers. d) if the farms nearby use chemical fertilizers that could be washed into the pond.

D)  If the farms nearby use chemical fertilizers that could be washed into the pond.

Explanation:

Algal bloom or eutrophication is a natural phenomena in which the excess increase of organic minerals such as phosphorus and sulfur inside the pond or any other water body promotes the growth of large number of aquatic plants and algae. This results in the depletion of oxygen in the water body. Hence, makes the aquatic habitat unsuitable for the survival of the aquatic animals like fishes.

This will be biased to say that the chemical fertilizers made in the factory near the pond responsible for the presence of chemicals in the water unless other sources of chemicals are not looked up near the pond. The agricultural fertilizers runoff can also be responsible for the phenomena of eutrophication as some chemical fertilizers like nitrogen, phosphorus, sulfur are present as essential ingredients in such fertilizers, which are washed away along with the water of irrigation into the pond.

the answer is c) abandoned properties that are contaminated with hazardous materials.