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 susceptible to radiations are: 
Select and explain. 
A. Nucleic acids, B. Nerve cells, C. Muscle cells, D. Epithelial cells
A: Nucleic acids
Answer: A: Nucleic acids 
Explanation: None