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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Most common cause of hyperparathyroidism: March 2009
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The correct answer is  Ans. C: Adenoma Hyperparathyroidism causes hypercalcemia through the excessive secretion of parathyroid hormone, usually by an adenoma (benign tumors) of the parathyroid glands (nearly 80%). Chief cell parathyroid hyperplasia accounts for nearly 15% cases.