求一道prep逻辑解答~~

sisleycheerup

24.    Tiger beetles are such fast runners that they can capture virtually any nonflying insect.  However, when running toward an insect, the beetles intermittently stop, and then, a moment later, resume their attack.  Perhaps they cannot maintain their pace and must pause for a moment's rest; but an alternative hypothesis is that while running tiger beetles are unable to process the resulting rapidly changing visual information, and so quickly go blind and stop.

Which of the following, if discovered in experiments using artificially moved prey insects, would support one of the two hypotheses and undermine the other?

(A) When a prey insect is moved directly toward a beetle that has been chasing it, the beetle immediately turns and runs away without its usual intermittent stopping.
(B) In pursuing a moving insect, the beetles usually respond immediately to changes in the insect's direction, and pause equally frequently whether the chase is up or down an incline.
(C) The beetles maintain a fixed time interval between pauses, although when an insect that had been stationary begins to flee, the beetle increases its speed after its next pause.
(D) If, when a beetle pauses, it has not gained on the insect it is pursuing, the beetle generally ends its pursuit.
(E) When an obstacle is suddenly introduced just in front of running beetles, the beetles sometimes stop immediately, but they never respond by running around the barrier.

我的简短理解：甲虫飞着飞着要停有两个可能的原因，一是调整步伐，二是调整视力，问哪个是削弱一个而支持另一个的例子，答案是C，麻烦解答一下啊~~谢谢~~~=^.^=

nesstang

甲虫飞着飞着要停有两个可能的原因，一是因为累的跑不动（体力论），二是调整视力（视力论）

(A) When a prey insect is moved directly toward a beetle that has been chasing it, the beetle immediately turns and runs away without its usual intermittent stopping.
当猎物面对beetle飞来时，beetle马上跑走，没有边飞边停。与题目条件不符

(B) In pursuing a moving insect, the beetles usually respond immediately to changes in the insect's direction, and pause equally frequently whether the chase is up or down an incline.
追猎物时，beetle根据猎物的位置变化马上转变（否定视力论），并且无论猎物上坡还是下坡都以一样的频率休息（否定体力论，假若支持累要休息，上坡休息应该更频繁）。此选项2个原因都否定了

(C) The beetles maintain a fixed time interval between pauses, although when an insect that had been stationary begins to flee, the beetle increases its speed after its next pause.
beetle休息之间的时间是固定的，尽管当一只静止不动的猎物准备逃跑时，beetle在下一次休息后会加快速度。每次飞的时间固定，但是会加速，否定了体力论（若支持体力论，速度快时飞的时间应该短）。支持了视力论，beetle体力没有问题，可还是要pause，其目的就是要定位，看准了方向再加速

(D) If, when a beetle pauses, it has not gained on the insect it is pursuing, the beetle generally ends its pursuit.
如果当beetle休息时，它还没有赶上它追的猎物，beetle就会结束追赶。无关项

(E) When an obstacle is suddenly introduced just in front of running beetles, the beetles sometimes stop immediately, but they never respond by running around the barrier.
当追赶过程中beetle前面有阻碍物时，beetle有时会立马停止，但是他们不会围障碍物转。无关项

sisleycheerup

哇好详细~~~完全明白了~~~谢谢~~~o(∩_∩)o..

gongbing66

看了楼上上的解释,我突然发现我对c选项弄反了,同感谢

DXDWSY

解释的好清楚，原文归纳也很精辟，赞一个