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
Most sensitive structure in cell for radiotherapy is – 
Select and explain. 
A. Cell membrane, B. Mitochondrial membrane, C. DNA, D. Enzymes
C: DNA
Answer: C: DNA 
Explanation: Clinical target for radiation induced cell death is DNA