阅读原文第二段：

To impose some order on this kaleidoscope of patterns， one school of thought proposes dividing populations into two groups. These ecologists posit that the relatively steady populations have density-dependent growth parameters that is， rates of birth， death， and migration which depend strongly on population density. The highly varying populations have density-independent growth parameters， with vital rates buffeted by environmental events these rates fluctuate in a way that is wholly independent of population density.

2.It can be inferred from the text that the author considers the dichotomy discussed to be

[A] applicable only to erratically fluctuating populations.

[B] instrumental， but only if its limitations are recognized.

[C] dangerously misleading in most circumstances.

[D] a complete and sufficient way to account for observed phenomena.

「答案」B

「考点解析」这是一道细节推导题。根据题干中的“dichotomy”可将本题的答案信息来源迅速确定在第二段的首句。如果考生能够正确理解该句中“but”一词前后的内容，就可以找出本题的正确选项B.考生在解题时一定要正确理解原文所传达的含义，即进行正确的细节推导。