In a uniformly expanding universe, which statement best describes the situation as viewed from an observer in Galaxy C (not the Milky Way Galaxy) ?

a. Galaxy C observer sees some galaxies moving away, some moving towards itself.

b. Galaxy C observer sees all galaxies moving away from the Milky Way Galaxy.

c. Galaxy C observer sees all other galaxies moving away from itself.

The correct answer is A

Explanation:

In a uniformly expanding universe, it is safe to assume that all the galaxies that are contained in it move away from each other. You could think of this as drawing dots on a balloon and notice how these grow apart as you fill the balloon with air.

However, you must not forget about physics in outer space, particularly the laws of gravitation. It is because of these forces of gravity that certain galaxies may seem to move towards others of greater size or, to be precise, of greater gravitational force.