What characterizes heat rash?

The correct answer is characterized by the appearance of a red, raised rash accompanied by prickling sensations on the skin. This condition, known as heat rash or miliaria, occurs when sweat ducts become blocked, leading to inflammation and an eruption of small blisters or red bumps on the skin. The prickling sensation is caused by sweat becoming trapped beneath the skin's surface, which can be quite uncomfortable, particularly in hot and humid conditions.

The other options do not accurately describe heat rash. A cold sensation on the skin would not typically be associated with heat rash, as it is fundamentally a response to heat and sweating. Extreme fatigue and dizziness are symptoms more related to heat exhaustion or heat stroke rather than a localized skin condition like heat rash. Lastly, sweating without discomfort does not capture the hallmark characteristics of heat rash, where discomfort and sensations of prickliness are prominent due to the trapped sweat.