As stated in the Big Bang theory, what does the REDSHIFT of light from galaxies indicate about our Universe?

Question

a
The universe is mainly hydrogen
b
The universe is cooling off.
c
The universe is expanding.
d
The universe is 13.8 billion years old.

Answer 1

The correct answer is:

c - The universe is expanding.

Redshift indicates that light from distant galaxies is shifting towards the red end of the spectrum, which is interpreted as those galaxies moving away from us. This observation supports the idea that the universe is expanding.