Which of the following is a sign of heat exhaustion?

• A. Dizziness
• B. Hot, dry skin
• C. Rapid pulse
• D. Decreasing urine output

Answer: (D)

Heat exhaustion stems from overheating plus fluid loss from sweating, leading to dehydration. When the body becomes dehydrated, the kidneys conserve water and produce less urine. That decreasing urine output directly signals the fluid imbalance central to heat exhaustion, making it the best sign among the options. Dizziness and a rapid pulse can occur with many conditions and aren’t as specifically tied to the dehydration aspect. Hot, dry skin points more to heat stroke, where the body’s cooling mechanism fails and the skin becomes dry and hot. So, reduced urine output most clearly reflects the dehydration component of heat exhaustion.