Which of the following is a symptom of heat exhaustion?

A weak and rapid pulse is a classic symptom of heat exhaustion due to the body's response to overheating. When the body temperature rises, the cardiovascular system must work harder to regulate temperature and maintain blood flow to vital organs. As a result, the pulse becomes weak and rapid as the heart attempts to pump more blood in an effort to cool the body down through processes like sweating and increased blood circulation to the skin.

This response is a key indicator that the individual is experiencing heat-related stress. In the case of heat exhaustion, the body is still able to sweat and cool down, but the rapid pulse reflects the increased physiological demand on the heart during this distress. Recognizing this symptom is crucial for timely intervention and preventing progression to more severe heat illnesses.