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
Prolonged administration of Sodium nitroprussside can cause poisoning of: 
Select and explain. 
A. Cyanide, B. Methanol, C. Arsenic, D. Phenol
A: Cyanide
Answer: A: Cyanide 
Explanation: Cyanide