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: Forensic Medicine
[{'content': 'Hypocalcemia is seen in poisoning of: March 2003 \nSelect and explain. \nA. Ammonia, B. Salicylates, C. Carbolic acid, D. Oxalic acid', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. D i.e. Oxalic acid', 'role': 'assistant'}]