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: Social & Preventive Medicine
. True about polio is all except: 
Select and explain. 
A. Sabin vaccine is attenuated, oral vaccine, B. Salk is a killed formalized vaccine used, C. Vaccine induced polio is usually due to Type 2 virus, D. Most common type of virus in epidemics is Type 1
C: Vaccine induced polio is usually due to Type 2 virus
Answer: C: Vaccine induced polio is usually due to Type 2 virus 
Explanation: Vaccine induced polio" is usually due to Type 2 virus