Which diseases are associated with a contagious condition?

The correct choice highlights diseases that are contagious, meaning they can be transmitted from one person to another. Conjunctivitis, commonly referred to as pink eye, is highly contagious and can spread through direct contact with the infected person's eye secretions. Tinea, often known as ringworm, is a fungal infection that spreads through skin-to-skin contact or by coming into contact with contaminated surfaces. Herpes simplex is a viral infection that is easily transmitted through skin contact, particularly during an outbreak.

In contrast, the other options consist of conditions that are not considered contagious. Skin tags, moles, and keratomas are benign growths that do not spread from person to person. Basal cell carcinoma and melanoma are types of skin cancer that arise from changes in skin cells, and these conditions are not contagious as they stem from internal factors such as genetics or sun exposure. Acne, milia, and seborrhea are skin-related issues primarily caused by hormonal changes and individual skin types rather than infectious agents, making them non-contagious as well.

Therefore, option D accurately identifies diseases that have the potential to spread between individuals, facilitating the understanding of contagious conditions in the context of esthetics and health.