The correct answer is "OI, II, and III."
Explanation:
I. The red shift in star spectra:
- The red shift in star spectra refers to the phenomenon where light from distant galaxies is shifted towards longer wavelengths, moving towards the red end of the spectrum.
- This red shift indicates that galaxies are moving away from us, supporting the expansion of the universe as predicted by the Big Bang Theory.
II. Microwave energy across the universe at approximately 3 degrees Kelvin:
- The discovery of the cosmic microwave background radiation, which is uniform and corresponds to a temperature of about 3 degrees Kelvin, provides strong evidence for the Big Bang Theory.
- This radiation is considered a remnant of the early universe and supports the idea of an initial hot, dense state followed by rapid expansion.
III. The abundance of light elements in the universe:
- The presence of light elements like hydrogen and helium in the universe in the proportions predicted by Big Bang nucleosynthesis is another piece of evidence supporting the theory.
- The synthesis of these light elements in the early universe aligns with the predictions of the Big Bang model, adding credibility to the theory.
Therefore, all three pieces of evidence - the red shift in star spectra, microwave background radiation, and the abundance of light elements - support the Big Bang Theory.
