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
Which of the following drug need not be stopped before surgery ? 
Select and explain. 
A. Aspirin, B. Warfarin, C. Metformin, D. Digitalis
D: Digitalis
Answer: D: Digitalis 
Explanation: Ans. is 'd' i.e., Digitalis