The correct option is A It prevents the movement of maternal IgG antibody from the mother of the foetus
The placenta is an organ that connects the developing fetus to the uterine wall to allow nutrient uptake, provide thermo-regulation to the fetus, waste elimination and gas exchange (acting as fetal lung) via the mother's blood supply, stores glycogen (acting as liver) fight against internal infections and produce hormone to support pregnancy (acting as endocrine gland).
IgG antibodies can pass through the human placenta, thereby providing protection to the fetus in the uterus. Maternal IgG can cross the placenta and provides immunity to the fetus.
Thus, the correct answer is option A.