GRE Reading Comprehension: JiJing 352-GRE阅读机经352篇 - 5NERNZ4786ZVY6DBJ

The primary purpose of the passage is to A. examine differences in the threats faced by marine and terrestrial ecosystems. B. explain how human intervention has affected marine and terrestrial ecosystems. C. discuss a distinguishing feature of marine ecosystems D. present a debate regarding the causes of marine ecosystem impermanence E. discuss certain consequences of marine ecosystem impermanence