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 held together by gravity within galaxies. C. Stars are constantly forming and dying. D. Light moves at a constant speed through empty space.

A.

Explanation:

The big bang theory states that at the beginning all the matter was compressed in a particle, that explodes and started to spread in the space. According to it, the universe couldn't be static, because the matter would still be spreading.

With telescopes, scientists could observe that some galaxies are moving far ways from the other, proving that the universe is not static. The starts being held together doesn't demonstrate the movement of the matter in the universe, and neither their formation nor dying, which only demonstrates that the matter is being "used".

The movement of the light at a constant speed is a characteristic of the light, and it doesn't demonstrate that the universe is or isn't static.