黃金閱讀 RUNNING WATER ON MARS - 英檢

But detractors maintain that the terraces could also have been created by
geological activity, perhaps related to the geologic forces that depressed
the Northern Hemisphere far below the level of the south, in which case they
have nothing whatever to do with Martian water.

9. Which of the sentences below best expresses the essential information in
the highlighted sentence in the passage? Incorrect choices change the meaning
in important ways or leave out essential information.
○But detractors argue that geological activity may be responsible for the
water associated with the terraces.
○But detractors argue that the terraces may have been formed by geological
activity rather than by the presence of water.
○But detractors argue that the terraces may be related to geological forces
in the Northern Hemisphere of Mars, rather than to Martian water in the south.
○But detractors argue that geological forces depressed the Northern
Hemisphere so far below the level of the south that the terraces could not
have been formed by water.


想請問
答案為何是2不是4?
其實我分辨不出來2跟4的差別
在我看來是覺得4說得比較詳盡
所以選4..請幫忙指導一下
感激

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