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
Non–depolarizing blockade is potentiated by : 
Select and explain. 
A. Hyperkalemia, B. Hypomagnesemia, C. Chronic phenytoin therapy, D. Quininidine
D: Quininidine
Answer: D: Quininidine 
Explanation: None