Since I was confused between (B) and (D), I want to clear below query.
B. 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.
D. Four hundred times larger than the Moon and 400 times farther away from Earth, the Sun has the same apparent size in the sky as the Moon's.
As mentioned by Ashish, option (D) is wrong because it doesn't maintain the causal relationship per the sentence.
As mentioned
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B. 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.
D. Four hundred times larger than the Moon and 400 times farther away from Earth, the Sun has the same apparent size in the sky as the Moon's.
As mentioned by Ashish, option (D) is wrong because it doesn't maintain the causal relationship per the sentence.
As mentioned
...
