请教OG11-77，紫皮

道光

77. Parasitic wasps lay their eggs directly into the eggs of various host insects in exactly the right numbers for any suitable size of host egg．If they laid too many eggs in a host egg，the developing wasp larvae would compete with each other to the death for nutrients and space．If too few eggs were laid，portions of the host egg would decay, killing the wasp larvae．

Which of the following conclusions can properly be drawn from the information above?

(A)  The size of the smallest host egg that a wasp could theoretically parasitize can be determined from the wasp's egg-laying behavior.

(B)  Host insects lack any effective defenses against the form of predation practiced by parasitic wasps．

(C)  Parasitic wasps learn from experience how many eggs to lay into the eggs of different host species．

(D)  Failure to lay enough eggs would lead to the death of the developing wasp larvae more quickly than would laying too many eggs．

(E)  Parasitic wasps use visual clues to calculate the size of a host egg．

答案选A。

我想不通的是，从题干第一句话看，无论如何都是host egg的大小来决定parasitic wasps产卵数量的多少，而不是反过来由parasitic wasps固定想要产卵多少个来决定它选择host egg的大小吧？

A选项明显就是wasps在选择host egg，而并非host egg决定wasps产卵数目了。。。

我选了个最平庸的C选项。。。起码这个满足了是host egg型号大小决定wasps产卵数量。。。

望高人指点~~~~~

[此贴子已经被作者于2008-9-24 11:05:30编辑过]

isMindy

不用管谁决定谁。

只要抓住Parasitic wasps在一个host egg里产卵的数量是和这个host egg的大小相匹配的这一点就可以。

A。可以从wasp's egg的laying behavior来推断出wasp理论上能够寄生的host egg的最小尺寸。 （在某个egg里产卵数最少，那么那个egg就是最小的）

C。文中没有提及任何关于experience的字段，你无法知道他们的这个behavior到底是learn from experience还是遗传，或是其他。

道光

谢过ls先。。。个么。。。但是。。。难道凡是这种关系的二者，都不用管谁决定与被决定蛮？。。。

zhuoxin_lee

egg-laying behavior这个词组也太抽象了

 我也是选错了，选了C

zhuoxin_lee

egg-laying behavior这个词组也太抽象了

 我也是选错了，选了C