Answer: Option A
:
A
A morula is an embryo at an early stage of embryonic development, consisting of cells (called blastomeres) in a solid ball contained within the zona pellucida. The morula is produced by embryonic cleavage, the rapid division of the zygote. The increase in the number of cells doesn't change the size of the original mass. The divisions are rapid because there is no net growth of the embryo. In the absence of growth, the cell number in the embryo increases while the cell size decreases. Thus, it has an almost equal quantity of cytoplasm as an uncleaved zygote but much more DNA.