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
QY prolongation can be caused by 
Select and explain. 
A. Lithium, B. Quinidine, C. Adenosine, D. Magnesium
B: Quinidine
Answer: B: Quinidine 
Explanation: None