What is a key indicator of frostbite on the ear?

Frostbite on the ear is primarily characterized by changes in skin color and the presence of lesions. In particular, affected areas may appear red initially, and as the condition progresses, the skin can develop blisters, which are indicative of tissue injury due to the freeze-thaw cycle. These lesions signal the extent of injury and are critical for an accurate assessment of frostbite severity.

The other options provide symptoms that do not accurately describe the typical clinical presentation of frostbite. For instance, swollen and painful responses are more commonly associated with injuries or inflammation rather than frostbite itself. Itchy and dry skin may occur in other dermatological conditions but do not align with the characteristics of frostbite. Similarly, warmth to the touch is not a sign of frostbite, as the affected area is typically cold and may feel numb or hard due to the freezing process. Thus, the appearance of red skin and lesions serves as a key indicator of frostbite on the ear.