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: Medicine
Tetany is not seen in: March 2005 
Select and explain. 
A. Malabsorption, B. Hyperventilation, C. Antiestrogen therapy, D. Thyroid Surgery
C: Antiestrogen therapy
Answer: C: Antiestrogen therapy 
Explanation: Ans. C: Antiestrogen therapy Causes of hypocalcemia: Hypoparathryoidism Hyperventilation Vitaminn D deficiency Acute pancreatitis Hypomagnesemia Small bowel resection Secondary hypoparathyroidism, including surgery of the thyroid/parathyroid, trauma, infection, burns, cancer Frequent vomiting Excessive ingestion of alkali Respiratory alkalosis Chronic alcoholism Small bowel bypass Strychnine Hyperaldosteronism Chelation of calcium Low Vitamin D, from causes such as malnutrition, malabsorption, kidney disease, infection and drugs Severe diarrheoa Low calcium diet