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': "Chadwick's sign is : \nSelect and explain. \nA. Intermittent urine contraction, B. Bluish discoloration of vagina, C. Vaginal pulsations, D. Softening of the cervix", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Bluish discoloration of vagina', 'role': 'assistant'}]