Which of the following can runoff from a residential area into a body of water eventually causing eutrophication?

Eutrophication is a significant environmental issue often linked to nutrient over-enrichment in aquatic ecosystems. When fertilizers and animal waste are washed off from residential areas into nearby bodies of water, they introduce high levels of nutrients, particularly nitrogen and phosphorus. These nutrients serve as fertilizers for algae and aquatic plants, leading to excessive growth, or algal blooms.

As these blooms die and decompose, it depletes the dissolved oxygen in the water, creating hypoxic or anoxic conditions that can harm or kill fish and other aquatic organisms. This process can lead to a decline in water quality, the death of aquatic life, and a shift in the overall ecosystem balance. Therefore, the runoff of fertilizers and animal waste is a primary contributor to eutrophication, highlighting the importance of managing such inputs in residential and agricultural settings to protect aquatic environments.

The other options, while they can cause various forms of pollution, do not directly contribute to the eutrophication process in the same way that fertilizers and animal waste do.