The correct option is A Passive immunity
In case of passive immunity, antibodies generated in one person are transferred to another individual, making the recipient immune to a disease he has never encountered. Transfer of antibodies that occurs from mother to foetus via the placenta is an example of natural passive immunity. Mother’s milk contains colostrum, a yellowish secretion, that contains antibodies against pathogens that the mother has been exposed to. Since these are transferred to the baby, this kind of immunity is termed as ‘passive immunity’.