Thank you Ashish!!
Can you please explain how B is correct?
If we remove the following clause
"which is 400 times larger than the Moon"
Sentence looks something as shown below.
The Sun, which is 400 times larger than the Moon, is also 400 times farther away from Earth,so the Sun and the Moon have the same apparent size in the sky.
The sun is ALSO 400 times farther away from Earth,so the Sun and the Moon have the same apparent size in the sky.
Don't you think it is awkward?
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