What is the most common injury caused by exposure to the cold?

Frostbite is indeed the correct response because it specifically refers to the localized damage to skin and other tissues that occurs due to exposure to cold temperatures. This injury typically affects extremities such as fingers, toes, ears, and the nose, where blood flow is decreased by cold, leading to ice crystal formation within cells and subsequent tissue damage.

While hypothermia is also a serious condition caused by prolonged exposure to cold, it affects the entire body and is characterized by a dangerously low body temperature rather than localized injury. Chilblains are minor injuries that occur due to an abnormal reaction to cold, typically resulting in itchy, red patches on the skin, but they are less common than frostbite. Altitude sickness is unrelated to cold exposure; it results from reduced oxygen levels at high altitudes. Thus, frostbite stands out as the most prevalent injury specifically tied to exposure to cold environments.