This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Physiology and Pathophysiology - Primary Hyperparathyroidism, Subject name: Surgery
Most common surgically repairable cause of hyperparathyroidism? 
Select and explain. 
A. Adenoma, B. Carcinoma, C. Hyperplasia, D. Renal disease
A: Adenoma
Answer: A: Adenoma 
Explanation: ANSWER: (A) AdenomaREF: Blueprints Surgery by Seth J. Karp, James Morris, David I. Soybel Page 85Hyperparathyroidism is the most common cause of surgically correctable hypercalcemia.Primary hyperparathyroidism is a surgical disease and operation is required for the hyperfunctioning gland (A single hyperfunctioning adenoma accounts for approximately 90% cases)Secondary hyperparathyroidism of renal disease is treated medically.Tertiary hyperparathyroidism due to autonomous parathyroid hyperplasia occasionally requires surgery.