This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Chemotherapy, Subject name: Pharmacology
Radiation protector drug in clinical use among the following is 
Select and explain. 
A. Amifostine, B. Cisplatin, C. Mesna, D. Tirapazamine
A: Amifostine
Answer: A: Amifostine 
Explanation: Amifostine is used therapeutically to reduce the incidence of neutropenia-related fever and infection induced by DNA-binding chemotherapeutic agents including alkylating agents and platinum-containing agents . It is also used to decrease the cumulative nephrotoxicity associated with platinum-containing agents. Amifostine is also indicated to reduce the incidence of xerostomia in patients undergoing radiotherapy for head and neck cancerReference: Perez and Brady&;s textbook of radiation oncology; 6th edition