The type of immunity that a foetus receives from the mother via the p…

The correct answer is Option (1) → Passive immunity

Immunity that the body builds by making its own antibodies, after meeting an antigen, is active immunity. When ready-made antibodies are given from outside, the immunity is passive. The foetus does not make these antibodies itself. They pass to it from the mother through the placenta, so the foetus has passive immunity. Colostrum given to a newborn is another example.

Option (1) Passive immunity — Correct. The antibodies are made by the mother and only handed over to the foetus. Protection is quick, but it does not last long because the foetus did not make the antibodies.

Option (2) Active immunity — Incorrect. Active immunity arises when the body itself meets antigens, by infection or vaccination, and produces its own antibodies. It is slow to develop. The foetus receives antibodies; it does not produce them.

Option (3) Non-specific immunity — Incorrect. Non-specific (innate) immunity is present from birth and works through barriers such as skin, stomach acid and phagocytes. Antibodies act against particular pathogens, so they belong to acquired immunity, not to non-specific immunity.

NCERT Extract:
Active and Passive Immunity – “When a host is exposed to antigens, which may be in the form of living or dead microbes or other proteins, antibodies are produced in the host body. This type of immunity is called active immunity. … When ready-made antibodies are directly given to protect the body against foreign agents, it is called passive immunity. … The foetus also receives some antibodies from their mother, through the placenta during pregnancy. These are some examples of passive immunity.”