In past centuries, many people believed in a static Universe—one that had existed forever without changing much, and one that would continue forever more or less as it is today.

Which of the following facts supports the big bang theory and disproves the static model of the Universe?
A.
Most galaxies appear to be moving away from each other.
B.
Stars are constantly forming and dying.
C.
Stars are held together by gravity within galaxies.
D.
Light moves at a constant speed through empty space.