Which of the following is an example of a bacterial skin disease?

Boils are indeed an example of a bacterial skin disease. They occur when hair follicles become infected, typically due to bacteria such as Staphylococcus aureus. This results in a painful, swollen lump filled with pus, which is the body's response to the infection. Boils can appear anywhere on the skin, but they are most common in areas where friction occurs, like the armpits, thighs, and buttocks.

In contrast, psoriasis, dermatitis, and eczema are not caused by bacterial infections. Psoriasis is an autoimmune condition that leads to rapid skin cell turnover and characteristic scaling. Dermatitis refers to inflammation of the skin which can result from various causes, including allergies and irritants, while eczema is a form of dermatitis characterized by dry, itchy skin that can be triggered by environmental factors or stress. Understanding the microbial basis of certain conditions like boils highlights the importance of recognizing and treating infections promptly to prevent complications.