The classic radiographic finding of subperiosteal bone resorption, most frequently observed on the radial aspect of the middle phalanges of the hand, is strongly associated with which condition?

Explanation:
The correct option is c. Subperiosteal bone resorption, particularly evident on the radial side of the middle phalanges of the index and middle fingers, is the pathognomonic radiographic hallmark of hyperparathyroidism (whether primary, secondary, or tertiary). This is driven by excessive parathyroid hormone directly stimulating osteoclastic activity. Reference: Bilezikian JP et al. Guidelines for the management of asymptomatic primary hyperparathyroidism. J Clin Endocrinol Metab.