A couple where both husband and wife are producing functional gametes, but the wife is still unable to conceive, is seeking medical aid

A couple where both husband and wife are producing functional gametes, but the wife is still unable to conceive, is seeking medical aid. Describe any one method that you can suggest to this couple to become happy parents.

Methods IVF/ZIFT/IUI :
IVF : Ova from wife and sperm from the husband is collected.
It is induced to formed zygote under laboratory conditions.
ZIFT : Zygote or early embryo are then transferred to the fallopian tube or into uterus to complete further development.
IUI : Semen collected from the husband is artificially introduced either into the vagina or into the uterus of the wife.