The stellar epoch, which we are still in today, began:
A) with the end of the quark epoch, when neutrons and protons fused into deuterium.
B) with the end of the lepton epoch, when neutrinos were formed and escaped from matter.
C) with the liberation of the dark energy.
D) about 100 million years after the Big Bang, with the making of galaxies.
E) about three billion years after the Big Bang, with Population I stars forming.
E
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