Multiple Choice
Which of these statements is a correct description of the expansion of the universe?
A) Spacetime is something real, with galaxies inside it; as spacetime expands, the galaxies (or superclusters of galaxies) are carried along by the expansion.
B) Space is a vacuum, but the vacuum has real properties; as galaxies (or superclusters of galaxies) hurtle outward, the expansion is gradually slowing down by the resistance of space to the passage of the galaxies.
C) Spacetime is static, but dark matter, which is concentrated in the outer part of the universe, pulls outward on the galaxies.
D) Space is a vacuum, which is really nothing at all; the galaxies (or superclusters of galaxies) are hurtling outward through this nothingness.
Correct Answer:

Verified
Correct Answer:
Verified
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