大家看看这题应该怎么理解

red1358

On Pacific islands, a newly arrived gecko species, the house gecko, is displacing the previously established mourning gecko in urban areas, but populations of the two species are more stable in rural areas far from human settlement.  The house gecko does not attack the mourning gecko, but in areas where insects congregate it prevents the mourning gecko from feeding on them.

Which of the following contributes most to an explanation of the difference between gecko populations in urban and rural areas?

This question did not ask the different populations between these two species, rather ask why the population is more stable in rural area than urban area?

(A) In urban areas, geckos are valued because they eat so many insects.
(B) Geckos defend territories against other members of the same species.
(C) House geckos that arrive on islands are carried there in boats and planes.
(D) In places where there are lighted buildings, insects tend to gather around the light.
(E) Mourning geckos are all females and reproduce asexually, but house geckos reproduce sexually.

答案是：D
The difference between gecko populations in urban and rural areas has something to do with the insects?
If insects gather around the light, will there be more gecko or less?

wwxavier

题目问的是要一个城里城外壁虎种群不一样的一个解释。
题目和选项都为已知信息的前提下， 先找无关
A.geckon是否value和城内外population没有联系，无关
B.geckon护不护领地问题和城内外population没有联系，无关
C.house geckon怎么来的和城内外population没有联系，无关
D.看似无关，但是题目信息里说了虫子与壁虎的事情，多少有些联系，留着
E.两种壁虎的繁殖方式，和Population沾边，留着。
深入分析(可能有点主观了我）
D.虫子向光抱团，house gecko可以不让M壁虎捕食哪些虫子，所以城市里的gecko population结构就是H>M，而城外H和M捕食机会是平等的所以gecko population结构是H=M。所以可以解释。
E.两种壁虎繁殖方式不一样，但是和城里城外没有联系，所以无法解释问题，是无关选项！