After fertilization, the zygote undergoes mitotic cleavage to form gastrula which attaches to the uterus and undergoes organogenesis.

After fertilization, the zygotes attach to the uterus and undergo mitotic cleavage to form morula which further divides to form blastula and undergoes gastrulation.

After fertilization, the zygote undergoes mitotic cleavage to form a morula and further divides to form a blastula which attaches to the uterus and undergoes gastrulation.

None of the above