This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Radiology
"Subperiosteal" Resorption and Thickness of skull is increased in: 
Select and explain. 
A. Rickets, B. Osteomalacia, C. Hyperparathyroidism, D. Thalassemia
C: Hyperparathyroidism
Answer: C: Hyperparathyroidism 
Explanation: Hyperparathyroidism