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
A 30 year old male from West Bengal presents to you with hyperkeratosis, and transverse nail lines, Most likely cause is - 
Select and explain. 
A. Chronic arsenic poisoning, B. Chronic lead poisoning, C. Chronic mercury poisoning, D. Acute arsenic poisoning
A: Chronic arsenic poisoning
Answer: A: Chronic arsenic poisoning 
Explanation: None