This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Chemotherapy: General Principles, Subject name: Pharmacology
Sodium 2-mercapto ethane sulfonate is used as a protective agent in: 
Select and explain. 
A. Radiotherapy, B. Cancer chemotherapy, C. Lithotripsy, D. Hepatic encephalopathy
B: Cancer chemotherapy
Answer: B: Cancer chemotherapy 
Explanation: Ans. (B) Cancer chemotherapy(Ref: KDT 8th/e p919)Sodium-2-mercapto ethane sulfonic acid (mesna) is used to ameliorate the hemorrhagic cystitis caused by cyclophosphamide and ifosfamide.