英语翻译Fossils of the coral Acrocora palmata that date from the

Fossils of the coral Acrocora palmata that date from the last period when glaciers grew and consequently spread from the polar regions are found at ocean depths far greater than those at which A.palmata can now survive.Therefore,although the fossilized
A.palmata appears indistinguishable from A.palmata now living,it must have differed in important respects to have been able to live in deep water.
这种珊瑚色藻类的化石随着冰川生长而逐渐从极地向外蔓延,这些化石发现的地方比活的藻类生活的海域要深很多.虽然活的和化石长的像,但是,他们能不能在深水里生活是区分他们的标志.
The argument depends on the assumption that
(A) no fossils of the coral A.palmata have been
found that date from periods when glaciers
were not spreading from the polar regions（在冰川没蔓延时,也没化石发现）
我觉得选这个
(B) geological disturbances since the last period
during which glaciers spread have caused no
major downward shift in the location of
A.palmata fossils（地理灾害没有让化石向下移动）
(C) A.palmata now live in shallow waters in most
of the same geographical regions as those in
which deep-lying A.palmata fossils have been
found（现在藻类生活在这些化石发现地的浅摊）
(D) A.palmata fossils have been found that date
from each of the periods during which glaciers
are known to have spread from the polar region（藻类被发现的日期是每一个冰川被认为从极地蔓延的时期）
　(E) A.palmata can live at greater depths where the
　ocean temperature is colder than they can
　where the ocean temperature is warmer（当海域温度更低,藻类可以生活在更深的地方）
再问： 答案是B。
再答： 我想了一下，的确是B 题目说要证明这个化石在下面的原因，是化石随着冰川生长下去的 他后面给的条件：这些化石发现的地方比活的藻类生活的海域要深很多。虽然活的和化石长的像，但是，他们能不能在深水里生活是区分他们的标志。 应该说化石不是因为活的游下去 然后变成了化石 B排除另一个原因，说明不是因为geological disturbances使得冰滑下去而下去的，隐含是因为冰生长下去的。 如果A是对的话，并不能说明冰grew之后，那个化石是怎么下去的