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
Methemoglobinemia is caused by : 
Select and explain. 
A. Prilocaine, B. Ropivacaine, C. Bupivacaine, D. Procaine
A: Prilocaine
Answer: A: Prilocaine 
Explanation: None