Which of the following indicates a potential fungal infection of the scalp?

A red patch of blisters can indicate a potential fungal infection of the scalp due to its symptomatic nature. Fungal infections often lead to inflammation and the formation of blisters as the body reacts to the infection. This type of reaction is typically associated with dermatophytosis, commonly known as ringworm, which can cause red, itchy patches on the scalp and is often accompanied by blisters, scaling, and hair loss.

In contrast, while an oily scalp may signal other conditions or even improper scalp hygiene, it is not specifically indicative of infection. Redness with itching can result from various causes including irritation, dermatitis, or allergic reactions, making it less specific to fungal infections. Flaky patches, which may result from dandruff, dry skin or conditions like psoriasis, do not necessarily indicate a fungal presence, though they can sometimes be present in fungal infections. The distinctly blistering nature of a red patch signifies a stronger indication of a potential fungal infection, aligning more closely with typical symptoms.