This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Toxicology - 3, Subject name: Forensic Medicine
The following is the symptom in: 
Select and explain. 
A. Arsenic poisoning, B. Mercury poisoning, C. Lead poisoning, D. Thallium poisoning
A: Arsenic poisoning
Answer: A: Arsenic poisoning 
Explanation: Aldrich mees line: White bands of opacity in nails of fingers and toes Mees lines (horizontal 1 to 2 mm white lines on the nails, also called transverse leukonychia) which occur from a disturbance in the nail matrix keratinization. Note: It usually takes at least 30 days for the Mees lines to become visible. It may be seen 4 to 6 weeks after an acute arsenic ingestion. These can also be seen in Thallium poisoning and Chemotherapy.