This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunization, Subject name: Pediatrics
Which of the following is called first immunization of the baby? 
Select and explain. 
A. Colostrum, B. Handing over the baby to mother, C. OPV, D. DPT + BCG
A: Colostrum
Answer: A: Colostrum 
Explanation: a. Colostrum(Ref: Ghai 8/e p 192)Colostrum is rich in immunoglobulins & other substances that protect the baby against infections; So, Colostrum is called the 'First immunization' of the baby.