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': "Halban's sign is seen in \nSelect and explain. \nA. Endometriosis, B. Adenomyosis, C. Cervical cancer, D. Endometrial cancer", 'role': 'user'}, {'content': "Answer: B \nExplanation: Halban's sign refers to tender, softened uterus on premenstrual bimanual examination in adenomyosis.", 'role': 'assistant'}]