GRE Reading Comprehension: JiJing 352-GRE阅读机经352篇 - 540SSC5034IAWL6JJ

The author of the passage implies that some endangered species are unlikely to migrate naturally to habitats better suited to their survival because A. climate change is making such habitats disappear B. few if any viable routes to such habitats exist C. the pace of natural migration is typically slower than the current pace of climate change D. their numbers are already below the thresholds necessary for the typically random processes of natural dispersal E. their dependency on their current habitats is too strong