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
Acts both as poison and antidote: NEET 13 
Select and explain. 
A. Copper sulfate, B. Mercuric chloride, C. Silver chloride, D. Thallium arsenate
A: Copper sulfate
Answer: A: Copper sulfate 
Explanation: Ans. Copper sulfate