Multiple Choice
What is the Great Wall?
A) It is a ridge on the Moon near the crater Birt.
B) It is the distance beyond which astronomers cannot view any more galaxies or even quasars.
C) It is a large sheet of galaxies.
D) It is the time before the universe started expanding, about which we can never know anything.
E) It is an enormous intergalactic cloud of dust and gas that hides more distant galaxies.
Correct Answer:

Verified
Correct Answer:
Verified
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