If a hiker, adequately hydrated, ascends rapidly from sea level to 14,000 feet in freezing temperatures without proper acclimatization, which consequence related to thermoregulation is most likely?

💡 Explanation

Rapid ascent to high altitude in freezing conditions leads to hypothermia, overriding the body's normal thermoregulatory set point. The hypothalamus attempts to raise the body temperature, but cannot adequately compensate because of extreme environmental conditions; therefore, the hypothalamic set-point is overridden, rather than resulting in sweating, vasodilation, or suppressed shivering.

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