Questions: Which of the following is a source of endocrine disruptors in aquatic ecosystems? reduced sediment loads the presence of medications taken by humans increased rainfall increased sunlight

The answer is the second one: the presence of medications taken by humans.

Explanation for each option:

1. Reduced sediment loads: This is not typically a source of endocrine disruptors. Sediment loads can affect water quality and habitat but are not directly linked to endocrine-disrupting chemicals.

2. The presence of medications taken by humans: Correct. Many medications, such as hormones and pharmaceuticals, can enter aquatic ecosystems through wastewater and are known to act as endocrine disruptors, affecting the hormonal systems of aquatic organisms.

3. Increased rainfall: While increased rainfall can lead to runoff that may carry pollutants into aquatic systems, it is not a direct source of endocrine disruptors. The disruptors themselves would need to be present in the runoff.

4. Increased sunlight: Sunlight itself is not a source of endocrine disruptors. It can influence the breakdown of certain chemicals in the environment but does not introduce endocrine-disrupting substances.

In summary, the presence of medications taken by humans is a known source of endocrine disruptors in aquatic ecosystems.