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
For teletherapy setup, all are used except – 
Select and explain. 
A. Iridium 127, B. Cobalt 60, C. Simulator, D. Computer
A: Iridium 127
Answer: A: Iridium 127 
Explanation: Iridium 192 is used in Brachytherapy (not in teletherapy).