Answer: A. Sweating.
Explanation:
When you exercise in the heat, your cooling system has to work harder. Your body sends more blood to your skin and away from your muscles.
Your body has sweat glads. When heat activates these sweat glands, these glands bring that water, along with the body's salt, to the surface of the skin as sweat. Once on the surface, the water evaporates. Water evaporating from the skin cools the body, keeping its temperature in a healthy range.
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