How does pollution impact aquatic ecosystems?

Pollution significantly disrupts aquatic ecosystems and degrades water quality, making this the correct answer. When pollutants such as chemicals, heavy metals, or excess nutrients enter water bodies, they can lead to a variety of harmful effects.

For instance, pollutants can introduce toxins that directly harm aquatic organisms, affecting their health, reproductive capabilities, and overall population dynamics. Additionally, pollution can lead to the proliferation of harmful algal blooms, which deplete oxygen levels in the water and create dead zones where aquatic life cannot survive. This degradation of the physical, chemical, and biological integrity of the water results in diminished biodiversity and altered food webs, ultimately harming the entire aquatic ecosystem.

Addressing the other options: Enhancing biodiversity or promoting growth of phytoplankton are not accurate effects of pollution, as these processes do not occur in a healthy and balanced ecosystem. Increased water temperature can occur as a result of pollution (like thermal pollution), but it is more an outcome of certain types of pollution rather than a direct impact on aquatic life overall. The primary impact of pollution remains the disruption and degradation of aquatic habitats.