Which of the following conditions is characterized by small, fluid-filled sacs on the skin?

The correct choice identifies vesicles, which are small, fluid-filled sacs that form within or on the surface of the skin. These are typically less than 1 centimeter in diameter and can arise from various conditions, such as allergic reactions, infections, or skin irritations.

Vesicles are significant in dermatology because they can indicate underlying health issues, such as viral infections (e.g., herpes simplex) or dermatoses. Understanding their characteristics helps cosmetologists recognize skin conditions that require special considerations during treatment.

Although similar in nature, bullae are larger fluid-filled sacs, usually over 1 centimeter in diameter, distinguishing them from vesicles. Blisters are a more general term that can describe both vesicles and bullae, but they don't provide the precise classification needed in this context. Follicles refer to the structures from which hair grows and do not describe fluid-filled sacs.