句子汰換的問題~ - 英檢

最近做到了一個題目,想請各位高手幫我解惑一下~

Observations have found that the black hole at the center of this galaxy M81,
which is believed to be 70 million times more massive than the sun, generates
energy and radiation as it pull gas inwards at a high speed.

(A) Watchers have discovered a black hole at the center of the galaxy, believed
to be bigger than the sun, which generate radiation as it eats
(B) Scientists have identified a black hole at the center of a galaxy; they
believe it is much more massive than the sun, which creates energy as it pull
its food in very quickly.
(C) There has been a discovery of a massive black hole in Milky Way, which is
huge, and this black hole eats a lot.
(D) A huge black hole at the center of a galaxy is belived to be 70 million
times larger than the sun; it generates energy as it pulls in gas in gas at a
high speed.

我的想法是這樣
Observations have found that the black hole at the center of this galaxy M81,
which(代替this galaxy M81) is believed to be 70 million times more massive
than the sun,(共用前面the black hole的主詞) generates energy and radiation
as it pull gas inwards at a high speed.
觀察家們發現了一個黑洞位於一個質量比太陽還大了 70 million倍的銀河系M81的中央,
而當這黑洞以很快的速度拉進氣體時會產生能量和輻射

(A)Watchers have discovered a black hole at the center of the galaxy, believed
to be bigger than the sun, (which generate radiation as it eats)
產生輻射的是黑洞不是太陽
(B) Scientists have identified a black hole at the center of a galaxy; they
believe (it is much more massive than the sun), which creates energy as it pull
its food in very quickly.
我覺得這邊的it是black hole所以也錯, 因為原句是說galaxy跟sun比較
(C) There has been a discovery of a massive black hole in Milky Way, which is
huge, and this (black hole eats a lot.)
原句也沒有說吃很多
(D) A huge black hole at the center of a galaxy (is belived to be 70 million
times larger than the sun); it generates energy as it pulls in gas in gas at a
high speed.
跟B好像,但本文是說galaxy跟sun比較,所以也錯

這樣不是都沒有答案了QQ

不過給的答案是B

想著想著一個早上就過了!!不過還是想不通...

還是我本文理解錯誤!!??

如果本文的which是指black hole就解了

可是which不是就是補述前面的名詞this galaxy?

希望各位強者能幫幫我打通任督二脈! Thx!

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