Why is untreated water from lakes rarely collected for drinking?

Untreated water from lakes is rarely collected for drinking primarily because it may be contaminated by animals. This contamination can include pathogens such as bacteria, viruses, and parasites that come from animal waste. These microorganisms can pose serious health risks to humans and require thorough treatment processes to ensure the water is safe for consumption.

In contrast, the other factors, while potentially relevant in specific contexts, do not address the critical concern of health and safety. For instance, water temperature, murkiness, or mineral content, while they can affect taste or clarity, are not primarily responsible for the serious health risks associated with untreated water. Ensuring that drinking water is free from harmful contaminants is the foremost concern when considering water treatment and safety.