How is sensitive skin generally defined?

Sensitive skin is typically characterized as skin that reacts easily to various products and environmental factors. This sensitivity can manifest in several ways, such as redness, itching, burning, or discomfort after using certain skincare products or when exposed to irritants like harsh weather, pollution, or allergens. Individuals with sensitive skin often have a compromised skin barrier, which makes the skin more susceptible to irritants and reactions.

The other options do not accurately capture the essence of sensitive skin. Aging skin refers to the effects of time and environmental damage, and while it can be sensitive, that characteristic alone does not define it. Similarly, acne-prone skin may experience sensitivity, but not all acne-prone skin is classified as sensitive. Finally, skin with a thicker texture may not inherently exhibit sensitivity; in fact, thicker skin may sometimes provide a natural barrier against irritants. Thus, option C is the most accurate definition, as it encompasses the reactive nature of sensitive skin to stimuli.