标题: 大全P338的问题。 [打印本页] 作者: lisiberry 时间: 2017-3-15 19:18 标题: 大全P338的问题。 20. 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.
OA：A
我选的C。为啥A正确呢。
作者: RRZZR 时间: 2017-3-15 23:45
这是一个must be true的问题：
把eggs of parasitic wasp想成是皮球，把host egg想成是 口袋。皮球的size是一定的（和你拳头一样大），host egg即口袋的size会根据口袋的种类不同而不同。
A就是说 我可以根据 在口袋里放了几个皮球 而判断 这种口袋的大概size
C不对因为题目里没有说wasp怎么知道放多少egg的；有可能因为是learn from experience，还有可能是born with the ability（基因决定）。所以不一定对，不选。 作者: lisiberry 时间: 2017-3-16 05:59