This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Types of vaccines, Subject name: Pediatrics
Zero dose of polio vaccine is given at: 
Select and explain. 
A. Before giving DPT, B. At bih, C. When child is having diarrhea, D. When child is having polio
B: At bih
Answer: B: At bih 
Explanation: - OPV zero dose: Given at bih / as early as possible within first 15 days of life. LATEST NATIONAL IMMUNIZATION SCHEDULE (NIS): 2019