Structure in Our Universe Evolved by Initially Forming

Structure in our universe evolved by initially forming

A) giant galaxies, some of which later fragmented into dwarf galaxies.
B) dwarf galaxies that later merged to form bigger galaxies.
C) individual, free-floating stars, that later aggregated to form galaxies.
D) hot dark matter that later cooled into cold dark matter.
E) all types and sizes of galaxies at the same time.