Which of the following is a common cause of dermatitis?

Allergens are indeed a common cause of dermatitis, which is an inflammatory skin condition that can manifest in various forms, such as atopic dermatitis, contact dermatitis, or seborrheic dermatitis. Dermatitis often occurs due to an external trigger that sensitizes the skin, leading to an inflammatory response. Allergens such as pollen, certain metals (like nickel), fragrances, or ingredients in skincare products can provoke hypersensitivity reactions in susceptible individuals, resulting in symptoms like redness, itching, and swelling.

While other factors such as fungal infections and genetic predispositions can also play a role in skin conditions, allergens are specifically known for their capacity to induce dermatitis through direct immune reactions in the skin. Fungal infections typically lead to different conditions such as tinea or ringworm, viruses are more associated with infectious diseases that may affect the skin but do not usually constitute dermatitis, and genetics can contribute to a person's overall susceptibility to skin disorders but are not direct causes of dermatitis episodes.