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: Forensic Medicine
[{'content': 'For diatoms test the best site for taking sample is \nSelect and explain. \nA. Lungs, B. Bone marrow in Ulna, C. Bone marrow in femur, D. Muscle', 'role': 'user'}, {'content': 'Answer: C \nExplanation: C i.e. Bone marrow in femur', 'role': 'assistant'}]