This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General obstetrics, Subject name: Anatomy
[{'content': 'Chadwick sign is seen in : \nSelect and explain. \nA. Cervix, B. Vagina, C. Uterus, D. Ovary', 'role': 'user'}, {'content': 'Answer: B \nExplanation: During pregnancy, due to increased vascularity and hyperemia there is bluish discoloration of vagina called as Chadwick sign. Ref: Datta Obs 9e pg 42.', 'role': 'assistant'}]