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': 'Which of the following is the most common site of secondaries in a case of choriocarcinoma? \nSelect and explain. \nA. Vagina, B. Urethra, C. Lung, D. Brain', 'role': 'user'}, {'content': 'Answer: C \nExplanation: In 75% of cases metastasis from choriocarcinoma occurs into the lungs and rest usually occurs in the vagina. Other organs which may also contain metastases are vulva, kidneys, liver, ovaries, brain and bowel.', 'role': 'assistant'}]