求助OG12-59

napoleon8424

59. In order to withstand tidal currents, juvenile horseshoe crabs frequently burrow in the sand. Such burrowing discourages barnacles from clinging to their shells. When fully grown, however, the crabs can readily withstand tidal currents without burrowing, and thus they acquire substantial populations of barnacles. Surprisingly, in areas where tidal currents are very weak, juvenile horseshoe crabs are found not to have signifi cant barnacle populations, even though they seldom burrow.
Which of the following, if true, most helps to explain the surprising fi nding?
Tidal currents do not themselves dislodge barnacles from the shells of horseshoe crabs.
(B) Barnacles most readily attach themselves to horseshoe crabs in areas where tidal currents are weakest.
(C) The strength of the tidal currents in a given location varies widely over the course of a day.
(D) A very large barnacle population can signifi cantly decrease the ability of a horseshoe crab tofi nd food.
(E) Until they are fully grown, horseshoe crabs shed their shells and grow new ones several times a year.

题目理解起来我都有点困难，哪位大侠可以先简单帮我翻译一下原文？？？然后再讲解一下？
谢谢各位大侠牛牛们的帮助~~~~~~~

gmatmba

题目大概是：幼马蹄蟹用打洞的方式抵抗潮汐的水流。这种行为不利于barnacle（应该是蟹的食物）这种东西粘附与它的壳上。而成年蟹不用打洞就很容易抵抗住潮汐的水流，所以能获得大量的b。但奇怪的是，在一些潮汐水流很小的 地方，人们发现幼蟹即使不需要打洞但依然很少能获得足够的b.

问题：下面哪个能解释这个奇怪的发现？
A. 不止潮汐水流一个因素影响b是否能够粘附在蟹壳上。
B. 在水流最弱的地方，b最容易粘附在蟹壳上。
C. 在一个地方的水流强度在一天中变化也是很大的。
D. 大量的b会很大程度上降低蟹获取食物的能力。
E. 直到完全长大之前，蟹每年都会脱壳再长出新壳几次。

这回是不是可以清晰些了？

napoleon8424

哎呀~~~恍然大悟啊~~谢谢谢谢 ~~翻译的哈清晰啊~~~做逻辑题最怕的就是题目看不懂了~~~看来词汇量还是太差啊。。。。。

anchoretes

我似乎还是不太理解E。虽然未成熟前，螃蟹脱壳是能不让B粘附在螃蟹壳上。但是我认为要使E能解释这个现象，必须要明确一个前提：这个海岸边上大部分都是未成熟的螃蟹。而如果这个海岸边上大部分都是成熟的螃蟹时，怎么能能说明B不多呢？

请大家指教！！！

EGHJUYMN

题目里面要求解释the surprising finding，即文章中的"surprisingly, in areas where

tidal currents are very weak, juvenile horseshoe crabs are found not to have

significant barnacle populations, even though they seldom burrow."说来说去，它问你

的地方和成熟螃蟹是没有关系的。文章里面也说了，"when fully grown, however, the crabs

can readily withstand tidal currents without burrowing, and thus they acquire

substantial populations of barnacles."成熟螃蟹上barnacles本来就很多，不需要你说明不

多。

xiaoaojiang

这道题我也想问，为什么A不对呢？？

EGHJUYMN

假设A成立，海浪不把crabs身上的barnacles冲走。那么在没有海浪或者海浪很弱的时候，crabs身上不应该满身都是barnacles吗？跟文章里面讲的"in areas where tidal currents are very weak, juvenile horseshoe crabs are found not to have significant barnacle populations, even though they seldom burrow"矛盾了吧。