Which of the following is a sign of heat exhaustion?

The correct answer is confusion. Confusion during heat exhaustion occurs as the body struggles to cope with excessive heat, leading to a breakdown in normal physiological functions. When the body overheats, it can affect mental clarity and cognitive function due to dehydration and electrolyte imbalances, presenting as confusion or disorientation. Recognizing confusion as a symptom of heat exhaustion is crucial because it signifies a more severe response to heat stress and indicates the need for immediate action to cool down and rehydrate.

The other symptoms listed may not directly relate to heat exhaustion. For instance, chills and shivering typically signal the body's attempt to generate heat, which contrasts with the overheating characteristic of heat exhaustion. Extreme thirst, while associated with dehydration, does not indicate confusion or the critical state of heat exhaustion as directly as confusion does. In essence, confusion is a clear indicator that immediate mitigation of heat exposure is necessary to prevent further complications.