This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous system, Subject name: Pharmacology
Which among the following drug is contra-indicated in renal failure? 
Select and explain. 
A. Pethidine, B. Morphine, C. Fentanyl, D. Atracurium
A: Pethidine
Answer: A: Pethidine 
Explanation: Renal failure patients given repeated doses of pethidine are prone to experience similar effects. All the other drugs are safe in renal failure. Ref: KD Tripathi 8th ed