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: Gynaecology & Obstetrics
[{'content': ". 35 year old mother of two children is suffering from amenorrhea from last 12 month. She has a history of failure of lactation following second delivery but remained asymptomatic thereafter. Skull X-ray shows empty sella diagnosis is: \nSelect and explain. \nA. Menopause, B. Pituitary tumor, C. Sheehan's syndrome, D. Intraductal papilloma of breast", 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]