The correct option is A age
In IVF, the woman is given medication to induce ovulation of several eggs in a cycle. These eggs are harvested and fertilized with sperm of the donor or the father. Fertilisation takes place in a culture dish designed to replicate the conditions in a woman’s uterus. Once the embryo has sufficiently matured, usually after 3 to 5 days, it is inserted into the uterus of the donor mother for further development.
ZIFT involves the same initial steps as IVF. These two procedures differ in the age of embryo transferred. In ZIFT, an 8 blastocyst embryo, formed after one day of division, is transferred into the fallopian tube which is the normal position for an embryo of this age in a natural conception.