Final answer:
The variations and fluctuations in the early universe facilitated the formation of stars and galaxies, with dark matter playing a crucial role in their development. The process relied on the 'just right' fluctuations in density and the finely balanced rate of universal expansion. Dark matter, though not fully understood, is central to current models of galactic evolution. option 4 is correct
Step-by-step explanation:
The variations and fluctuations in the baby universe allowed for the formation of stars and galaxies. The initial distribution of matter, which included both luminous and dark matter, wasn't perfectly uniform, leading to the density fluctuations that are key to understanding galaxy formation.
As these fluctuations occurred in the early universe, smaller structures eventually merged to form larger galaxies, and dark matter played a critical role in this process. Astronomers recognize that while we do not fully understand the nature of dark matter, it is essential to our current models of galaxy formation and evolution - the number of stars we observe may be much less than the original matter created in the Big Bang.
Furthermore, without the presence of dark matter, the process of galaxy formation would have been significantly different. Dark matter's gravitational effects have been detected through various means, such as gravitational lensing, where the bending of light from distant objects indicates the presence of unseen mass. Although there is much more dark matter than luminous matter, its exact composition remains one of the great mysteries in physics. option 4 is correct