Which of the following is not a benign physiological variant?

Cheilosis, also known as angular cheilitis, is characterized by the presence of fissures or cracks at the corners of the mouth, which can be caused by various underlying factors such as nutritional deficiencies (especially riboflavin, niacin, and iron), infections, or irritants. Unlike the other conditions listed, cheilosis often indicates an underlying health issue that may require intervention to address the cause, rather than being merely a benign variant that typically resolves on its own without treatment.

In contrast, internal tibial torsion, supernumerary nipples, and split uvula are all considered benign anatomical variations that do not typically pose health risks or require treatment. Internal tibial torsion involves a twist in the tibia that commonly presents in children but often corrects itself as they grow. Supernumerary nipples are extra nipples that some individuals may have and are usually not associated with health problems. Split uvula, which results in a bifid or cleft uvula, is another benign physiological variant that rarely affects function or health.

This distinction highlights that while physiological variants exist, they are generally harmless and do not require medical intervention, unlike conditions such as cheilosis, which might signal a need for further evaluation and treatment.