During embryogenesis the zygote undergoes
a)	Cell division (mitosis)	b)	Cell division (meiosis)
c)	Cell differentiation	d)	(a) followed by (c)

(d)

After forming the zygote it under goes successive cleavage and becomes mass of cells. Cleavage is considered as mitosis without resting phase.

As in nature in the process of mitosis the genetic constitution remains the same hence, resulting all cells have similar genetic constitution. Cleavage is followed by cell differentiation processes like gastrulation, etc., which finally gives rise to different body parts