Which substance contributes to aesthetic issues and turbidity in water?

Suspended solids are particles that are not dissolved in water and can include a wide variety of materials such as dirt, silt, clay, organic matter, and other particulates. Their presence in water contributes significantly to aesthetic issues by affecting its clarity and color, often leading to a murky or cloudy appearance. Turbidity, which refers to the cloudiness or haziness caused by suspended particles, can not only affect the visual appeal of water but can also interfere with aquatic life and water treatment processes.

Unlike heavy metals, pathogens, and nutrients, which have their own distinct impacts on water quality, suspended solids specifically create turbidity that can be easily observed. Heavy metals might pose health risks and environmental concerns, but they do not typically cause the visual issues associated with turbidity. Pathogens can lead to health problems but are not related to water's aesthetic qualities. Nutrients, while potentially causing issues like algal blooms, do not directly contribute to turbidity in the same way that suspended solids do. Thus, suspended solids are the primary contributors to aesthetic issues and turbidity in water, making them the correct answer.