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': 'Most sensitive structure in cell for radiotherapy is – \nSelect and explain. \nA. Cell membrane, B. Mitochondrial membrane, C. DNA, D. Enzymes', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Clinical target for radiation induced cell death is DNA', 'role': 'assistant'}]