1.        GWD-8-Q33***:

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 significant barnacle populations, even though they seldom burrow.

Which of the following, if true, most helps to explain the surprising finding?

A. 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 significantly decrease the ability of a horseshoe crab to find food.

E. Until they are fully grown, horseshoe crabs shed their shells and grow new ones several times a year.

答案是E,他因解释

我查完单词也没理解，请XDJM帮忙用中文阐述下逻辑关系，谢谢

jh crabs 为了withstand tidal currents所以frequently burrow in the sand.

但这种burrow的动作会使barnacles不能沾附在crabs

然而当crabs长大可以抵抗tidal currents

但应该会造成很多barnacles沾附在crabs上

Surprisingly在tidal currents are very weak的地方

jh crabs身上却无barnacles沾附even though they seldom burrow.

找帮助解释……..只有E可解………

谢谢,按解释矛盾来，好象就明白点了

现象解释: tide weak-> do not burrow in the sand   但是shell 上的 barnacle 少?    

  E 能解释, 由于crab  的shell 一年要更换几次, 所以每次换新的shell 上面的barnacle 就少了.

不知对否?

恩，好像e比较讲得通

这道题也错了。。。哎 GWD很打击人啊