Which observation helped scientists determine the age of the universe?
A. All stars and galaxies are moving closer together at the same rate.
B. All stars and galaxies are moving away from Earth at the same
rate.
OC. The farther away a star or galaxy is, the more slowly it is moving
away from us.
ะพ D. The farther away a star or galaxy is, the more quickly it is moving
away from us.