Question

which of the following is a piece of evidence in favor of the current big bang theory? more distant galaxies appear younger than nearby galaxies the night sky is dark (olbers paradox) the cosmic background radiation exists & is -3 k in temperature, as expected the universes chemical composition is -75% hydrogen & -25% helium by mass all of these

Explanation:

1. Distant galaxies appearing younger supports the idea of an expanding universe from a single - point origin.
2. Olber's paradox (dark night - sky) is resolved by the finite age and expansion of the universe in the Big Bang model.
3. Cosmic background radiation is a key prediction and evidence of the Big Bang, representing the "after - glow" of the early hot universe.
4. The observed chemical composition of the universe (75% hydrogen and 25% helium by mass) is consistent with the predictions of Big Bang nucleosynthesis.

Answer:

E. all of these