Which of the qualities listed below explain why certain organisms are classified as indicator species? They are a primary food source for many other organisms B. They are very sensitive to environmental change. C. They can't easily escape pollutants D. All the above

B. They are very sensitive to environmental change

Explanation:

Certain organisms like plants, animals and microbes are used to monitor pollution status of the environment. These organisms are called indicator species or bioindicators. They are widely used for pollution monitoring due to their sensitivity to environmental changes i.e. in the presence of a pollutant, they undergo morphological or physiological changes.

A common example of indicator species is the proliferation of algal species in a water body known as ALGAL BLOOM. They tend to grow excessively in the presence of pollutants in form of nitrates and phosphates which they use as nutrient.

i think that c)gold was found there

but i am not sure