What are the signs of dehydration?

The signs of dehydration are critical for maintaining overall health, as dehydration can lead to numerous health issues. The correct choice includes signs that accurately reflect the body's response to a lack of adequate fluids.

Thirst is one of the body's primary signals indicating a need for more water intake. It serves as a warning sign that the body is beginning to experience fluid deficiency. A dry mouth is a direct consequence of reduced saliva production, which occurs when the body is dehydrated. Fatigue is another common sign, as the body loses energy when it doesn't have enough fluids to function properly. Dark yellow urine indicates concentrated urine, which typically occurs when the body is retaining water due to dehydration.

The other options include either incorrect symptoms or actions associated with adequate hydration. For instance, signs such as increased energy or feelings of being energized do not correlate with dehydration; in fact, dehydration usually results in fatigue and reduced energy levels. Similarly, headaches can indicate dehydration, but they are not sufficient indicators on their own, as they can also arise from other conditions. Understanding these signs is essential for recognizing when to increase fluid intake and maintain proper hydration.