This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Human identification, Subject name: Forensic Medicine
Patient's relative gives a history of tattoo, however it was not found during autopsy. What should be dissected to find it: 
Select and explain. 
A. Lymph node, B. Skin, C. Spleen, D. Kidney
A: Lymph node
Answer: A: Lymph node 
Explanation: Tattoo Marks Faint or disappeared tattoo marks can be made out on histological study of the regional lymph nodesQ. In Decomposed bodies,they are made visible by treating the area with 3 %hydrogen peroxideQ.