A、Face. B、Knees. C、Arms. D、Feet. D题目问的是身体的哪一部分经常会冻伤。由定位句可知，冻伤主要发生在手、脚、鼻子和耳朵。故选D。

Frostbite is the damage that happens when skin is exposed to extreme cold for too long. It mainly happens on the hands, feet, nose and ears. People with minor cases of frostbite that affect only the skin may not suffer any permanent damage. But if deeper tissue is affected, a person is likely to feel pain every time the area gets cold. Sometimes the only way doctors can treat an injury like this is to remove frostbitten areas like fingers and toes.
    To avoid cold-related injuries, here is a simple way to stay warm. Wear a hat and scarf to keep heat from escaping through the head, the neck and the ears. And wear mittens instead of gloves. In gloves, the fingers are separated, so the hands might not stay as warm as they would in mittens. A-void activities that will make you sweaty. Wet clothes and cold weather are a dangerous combination. Wearing loose, lightweight clothes, one layer on top of another, is better than wearing a single heavy layer of clothing.
    Q25: In which part of the body does frostbite usually happen?
    Q26: What do doctors sometimes have to do if the frostbitten area is hurt too badly?
    Q27: Why are mittens better than gloves?