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: Radiology
[{'content': 'The most radiosensitive tissue is: March 2011 \nSelect and explain. \nA. Nerve, B. Bone marrow, C. Thyroid, D. Liver', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. B: Bone marrow Bone is among the most radioresistant organ By contrast, the male testis, female ovary, and bone marrow are the most sensitive organs Most Radiosensitive: Phase of cell cycle: G2M phase Structure in cell: DNA Cell: Lymphocyte Lung tumour: Small cell Ca Brain tumour: Medulloblastoma Ovarian tumour: Dysgerminoma Testicular tumour: Seminoma Bone tumour: Ewing's sarcoma Radioresistance: Cailage is radioresistant structure", 'role': 'assistant'}]