Erythroblastosis foetalis can be avoided by administering :
1) anti-Rh antibodies to the foetus
2) anti-Rh antibodies to the mother immediately after the delivery of 2nd child
3) anti-Rh antibodies to the mother immediately after the delivery of first child
4) More than 1✔
3) anti-Rh antibodies to the mother immediately after the delivery of first child