36篇E3一道经典问题终于搞明白了

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A mysterious phenomenon is the ability of over-water
migrants to travel on course. Birds, bees, and other
species can keep track of time without any sensory cues
from the outside world, and such ―biological clocks∥
5 clearly contribute to their ―compass sense.∥ For example,
they can use the position of the Sun or stars, along with
the time of day, to find north. But compass sense alone
cannot explain how birds navigate the ocean: after a flock
traveling east is blown far south by a storm, it will
10 assume the proper northeasterly course to compensate.
Perhaps, some scientists thought, migrants determine
their geographic position on Earth by celestial navigation,
almost as human navigators use stars and planets, but this
would demand of the animals a fantastic map sense.
15 Researchers now know that some species have a magnetic
sense, which might allow migrants to determine their
geographic location by detecting variations in the strength
of the Earth‘s magnetic field.

8. Of the following descriptions of migrating
animals, which most strongly suggests that the
animals are depending on magnetic cues to orient
themselves?
(A) Pigeons can properly readjust their course
even when flying long distances through
exceedingly dense fogs.
(B) Bison are able to reach their destination by
passing through a landscape that has
been partially altered by a recent fire.
(C) Elephants are able to find grounds that
some members of the herd have never seen
before.
(D) Swallows are able to return to a given spot
at the same time every year.
(E) Monarch butterflies coming from different
parts of North America are able to arrive
at the same location each winter.
这道题我一开始的思路是回原文定位到最后一句“Researchers now know that some species have a magnetic
sense, which might allow migrants to determine their
geographic location by detecting variations in the strength
of the Earth‘s magnetic field.” 那么解题点就应该是长距离，多样性，和磁场。但是这样的话，选项中都没有直接对应的。所以这道题的解题思路应该跨得更远，要从全文着手，全文讲了几种导航方法，或者依靠太阳，或者是其他天体，唯独磁场这种方法不需要这些，那么只有A符合了。如此这般，36篇的官方解答“A, 提到了调整航向，正确”，显然不是正确的解题思路。