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
Radiation mediates its effect by 
Select and explain. 
A. Denaturation of DNA, B. Ionization of the molecules, C. Protein coagulation, D. Osmolysis of cells
A: Denaturation of DNA
Answer: A: Denaturation of DNA 
Explanation: Ans. Denaturation of DNA