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: Dental
Absorption of mercury in the human body occurs least from 
Select and explain. 
A. Lungs, B. Gastro-intestinal Tract, C. Skin, D. Kidneys
D: Kidneys
Answer: D: Kidneys 
Explanation: None