Answer: Option D
:
D
Passive immunityis the transfer of antibodiesgenerated in a person, to another individual. This confers the recipient with immunity to a disease that the person hasnot encountered. Passive immunity is naturally transferred to breast-fed babies from their mother's milk. Breast milk has colostrum that contains antibodies against pathogens the mother has been exposed to. Transfer of antibodies that occurs from mother to foetus via the placenta is also an example here. Yet another application of this type of immunityis in the case of snake bites or other poisoning, wherein the immunity has to be conferred immediately and hence, readymade antitoxins are administered to confer passive immunity.