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
Industrial worker with blue lines on gums. Most probably due to: JIPMER 13 
Select and explain. 
A. Arsenic poisoning, B. Lead poisoning, C. Mercury poisoning, D. Copper poisoning
B: Lead poisoning
Answer: B: Lead poisoning 
Explanation: Ans. Lead poisoning