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: Pharmacology
BAL is contraindicated in 
Select and explain. 
A. Arsenic, B. Lead, C. Mercury, D. Iron
D: Iron
Answer: D: Iron 
Explanation: BAL or Dimercaprol is a chelating agent used to treat poisoning by Arsenic, Lead, Mercury and Gold. 
It is contraindicated in Iron & Cadmium poisoning.