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: Physiology
Cause of methaemoglobinemia are all except : 
Select and explain. 
A. Nitrites, B. Phenacetin, C. Sulfonamide, D. Phenytoin
D: Phenytoin
Answer: D: Phenytoin 
Explanation: D i.e. Phenytoin