The correct option is C Zygote intra fallopian transfer (ZIFT)
Childless couples could be assisted to have children through assisted reproductive structure through certain special techniques commonly known as assisted reproductive technologies (ART). In vitro fertilisation, (fertilisation outside the body in almost similar conditions as that in the body followed by embryo transfer) is one of such methods. In this method, popularly known as test tube baby programme, ova from the wife/donor (female) and sperms from the husband/donor (male) are collected and are induced to form zygote under simulated conditions in the laboratory. The zygote or early embryos (with upto 8 blastomeres) could then be transferred into the fallopian tube (ZIFT zygote intra fallopian transfer) and embryos with more than 8 blastomeres, into the uterus (intrauterine transfer), to complete its further development. Embryos formed by in vivo fertilisation (fusion of gametes within the female) also could be used for such transfer to assist those females who cannot conceive.