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': 'Weight of placenta at term: March 2013 \nSelect and explain. \nA. 300 grams, B. 400 grams, C. 500 grams, D. 600 grams', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. C i.e. 500 grams', 'role': 'assistant'}]