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
Which of the following represents the half life of I123 ? 
Select and explain. 
A. 3. 2 hours, B. 13.2 hours, C. 8 days, D. 10 days
B: 13.2 hours
Answer: B: 13.2 hours 
Explanation: Half life of radioisotope I 123 is 13.2 hours. Half life of I 124 is 4.2 days and that of I 131 is 8days.