Conservationists have believed that by concentrating their preservation efforts on habitats rich in an easily surveyed group of species, such as birds, they would thereby be preserving areas rich in overall species diversity. This belief rests on a view that a geographical area rich in one group of species will also be rich in the other groups characteristic of the entire regional climate zone.
Which of the following findings about widely scattered tracts 10 kilometers by 10 kilometers in a temperate climate zone would most seriously challenge the conservationists' assumptions?
(A) The tracts show little damage from human intrusion and from pollution by human activities.
(B) Where a certain group of species, such as birds, is abundant, there is also an abundance of the species, such as insects, on which that group of species feeds, or in the case of plants, of the land and water resources it requires.
(C) The area of one of the tracts is generally large enough to contain a representative sample of the organisms in the region.
(D) There is little overlap between the list of tracts that are rich in species of butterflies and the list of those that are rich in species of birds.
(E) The highest concentration of individuals of rare species is found where the general diversity of species is greatest.
logic book style :
P: This belief rests on a view that a geographical area rich in one group of species will also be rich in the other groups characteristic of the entire regional climate zone.
C : Conservationists have believed that by concentrating their preservation efforts on habitats rich in an easily surveyed group of species, such as birds, they would thereby be preserving areas rich in overall species diversity.
中文版本：
前提：一個物種多，其他物種也會多，在全氣候區間中
結論：用鳥這類好調查的物種，去保持多樣性
連貫性：有一個在，其他就跟著存在
本題題目問到challenge就是要來對結論質疑，所以可以被質疑，表示加上選項的這段話之後，結論的描述是可以瞬間從對的變成錯的，一般來說數學課本裡面那個若Ｐ則Ｑ，非Ｑ則非Ｐ的那些表格把它背一背，還有那個真假表，多少都有幫助。
選項分析：
(A) The tracts show little damage from human intrusion and from pollution by human activities.
沒威脅，所以生物依舊在，但題目中『挑戰』的用意就是要讓結論從preserving變成不能preserving，不能diversity，所以刪除
(B) Where a certain group of species, such as birds, is abundant, there is also an abundance of the species, such as insects, on which that group of species feeds, or in the case of plants, of the land and water resources it requires.
對結論補充diversity
(C) The area of one of the tracts is generally large enough to contain a representative sample of the organisms in the region.
表示空間的陳述，跟本文的連貫性無法連接
(D) There is little overlap between the list of tracts that are rich in species of butterflies and the list of those that are rich in species of birds.
little overlap＝no diversity，並且跟文章的連貫性是相『反』的
(E) The highest concentration of individuals of rare species is found where the general diversity of species is greatest.
稀有物種的最聚集處就是生物多樣性的最大處，這個將結論的diversity推大極致
選（Ｄ）
以上個人筆記希望有幫助到大家，有誤再請指教!!
托福TOEFL ibt (4)