Anti-A, anti-B, antibody appear in child -

Ans. is 'd' i.e.. After 6 months o litre of anti-A and anti-B antibodies is almost zero immedietly after birth.o Infants start producing anti-A and anti-B antibodies at age of 2-8 month when corresponding antigen is not present in cell.o Maximum titre rech at 8 to 10 years of age after that it started declinning.