Embryogenesis

[tnnn]

I was working through a bunch of questions. But one of them I could not seem to get my mind across.

Of the main processes in embryogenesis, which begins first?
a)Programmed Cell Death
b)Cell differentiation.
c)Cell proliferation.
d)Cell migration.

I don't think it is programmed cell death, nor cell migration. I am thinking between differentiation and proliferation. I know that zygotes undergo cleavage, and that increases the amount of cells, but does not effect the size overall. So perhaps differentiation?

I am not very sure. I anxiously await for your responses, it's getting on my nerves. Thanks.

[JackBean]

I think that proliferation is the division, not necessarily related to growth in volume, isn't it? The differentiation will be one of last.

[tnnn]

Thanks, so proliferation it is.

[tnnn]

Although, any further replies explaining why its proliferation first would be appreciated. Is it because cells need to proliferate before they start to differentiate? (Just by logic)