Which nutrient is commonly associated with the process of eutrophication?

Eutrophication is a natural process that can be accelerated by human activities, leading to excessive growth of algae in water bodies. The common nutrient associated with this phenomenon is phosphates, but nitrogen and organic carbon also play significant roles.

Phosphates, often originating from fertilizers, detergents, and wastewater, are nutrient-rich compounds that promote algal blooms. When algae die and decompose, they consume oxygen, leading to hypoxic conditions detrimental to aquatic life. Similarly, nitrogen, which can come from agricultural runoff, sewage, and atmospheric deposition, acts as a nutrient that contributes to the growth of algae alongside phosphates. Organic carbon is a component of many organic nutrients and can also enhance microbial growth and activity when present in excess, thus also contributing to the process of eutrophication.

Given that all these nutrients can contribute to the enrichment of water bodies, leading to eutrophication, the correct response encompasses all three. Therefore, the assertion that all of them are commonly associated with the process is valid.