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: Forensic Medicine
Nails and hairs are commonly preserved in: 
Select and explain. 
A. Acute lead poisoning, B. Acute arsenic poisoning, C. Chronic arsenic poisoning, D. All of the above
C: Chronic arsenic poisoning
Answer: C: Chronic arsenic poisoning 
Explanation: Chronic arsenic poisoning