Which of the following is a symptom of heat exhaustion?

Muscle cramps are indeed a symptom of heat exhaustion, which arises when the body is unable to cool itself adequately during exposure to high temperatures or excessive physical activity. This condition can lead to a loss of salt and fluid through sweating, resulting in muscle cramps, particularly in the legs and abdomen.

The association with heat exhaustion stems from the body's attempt to regulate temperature, which can deplete necessary electrolytes and cause discomfort and pain in the muscles. Recognizing these cramps as a symptom is crucial, as they signal the need for immediate attention to prevent the progression to more severe heat-related illnesses.

Other mentioned symptoms, such as high fever, rapid heart rate, and dry mouth, may also occur in heat-related disorders, but they are more commonly associated with other medical issues or severe heat stroke rather than heat exhaustion itself.