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': 'Premature menopause is when menopause occurs before \nSelect and explain. \nA. 55 years, B. 50 years, C. 45 years, D. 40 years', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Premature menopause is when menopause occurs before 45 years.', 'role': 'assistant'}]