What are common indicators of water contamination?

The correct choice focuses on unusual color, odor, taste, and sediments as common indicators of water contamination. These characteristics can signify that water is unsafe for drinking or other uses.

Unusual color in water may indicate the presence of contaminants such as metals, chemicals, or organic materials. Odor changes can suggest the presence of harmful substances, such as hydrocarbons or biological growth, which may not only be unpleasant but also pose health risks. A noticeable taste can also be a red flag, as certain contaminants can impart flavors that are distinct from clean water. The presence of sediments may denote particulate matter that could include harmful bacteria, viruses, or toxins, indicating the water's potential unfitness for consumption.

Other options may touch on related characteristics but don't specifically encompass the array of sensory indicators that are most effective in identifying water contamination. For example, temperature fluctuations and bubbles don't provide a comprehensive assessment of contamination, and while filtration time and clarity can be useful metrics in water treatment, they do not directly indicate contamination in the same immediate way that sensory indicators do.