The correct option is D Inner cell mass
Daughter cells formed by the mitotic division of the zygote are called blastomeres. Embryos consisting of 8-16 blastomeres are called morula. Morula further divides into blastocyst. Blastomeres in the blastocyst are arranged into two parts.
1. An outer layer called trophoblast.
2. Inner cell mass which consists of stem cells that divide and differentiate to form germ layers.