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: Radiology
[{'content': 'The radiation tolerance of whole liver is: \nSelect and explain. \nA. 15 Gy, B. 30 Gy, C. 40 Gy, D. 45 Gy', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Maximal tolerance dose (TD50/5) of liver is 40 Gy. Ref: X. Allen Li (2011), Chapter 20, "Adaptive Radiation Therapy for Liver Cancer", In the Book, "Adaptive Radiation Therapy", USA, Page 317 ; Clinical Radiation Oncology By Gunderson and Tepper, Page 715', 'role': 'assistant'}]