Heat stroke occurs when...

• A. The body's temperature regulation fails, and the body is unable to get rid of excess heat
• B. It occurs during cold weather
• C. When evaporation increases
• D. When core temperature drops

Answer: (A)

Heat stroke occurs when the body's temperature regulation fails and the body is unable to get rid of excess heat. Normally, sweating and increasing blood flow to the skin help dissipate heat, but when those cooling mechanisms are overwhelmed or impaired, core temperature rises rapidly to dangerous levels. This makes heat stroke a medical emergency, since high core temperatures can damage organs and brain function.

The other statements don’t fit because heat stroke is not caused by cold weather, and evaporation is a cooling process that helps prevent heat stroke rather than cause it. A drop in core temperature describes hypothermia, not heat stroke.