What ocular finding in a 72-year-old patient is most consistent with arcus senilis?

Arcus senilis is characterized by a distinct ring of gray or white around the corneal periphery, which is particularly common in older adults. This finding is due to lipid deposition in the corneal stroma and is generally considered a benign sign of aging rather than a pathological condition. In a 72-year-old patient, the presence of this specific ocular finding aligns directly with the features of arcus senilis, suggesting normal aging processes related to the eye.

Other options, such as corneal abrasion, corneal ulcer, and herpetic infection of the eye, relate to various conditions that can occur in the eye but do not describe the unique appearance or etiology of arcus senilis. Corneal abrasions and ulcers are injuries or infections that present with symptoms like pain and redness, while a herpetic infection would typically show different signs such as vesicular lesions and might affect visual acuity differently. Therefore, the presence of arcus senilis is the hallmark finding that confirms its diagnosis in an older adult.