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': 'Choriocarcinoma metastasizes most commonly to: March 2012 \nSelect and explain. \nA. Vagina, B. Lungs, C. Liver, D. Brain', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans: B i.e. Lungs Metastasis of choriocarcinoma Vaginal metastases forms in 30% of cases of choriocarcinoma The most common metastases in choriocarcinoma are seen in lungs (80%), brain and liver (10%).', 'role': 'assistant'}]