GRE Reading Comprehension: Maggoosh-GRE阅读Maggoosh - WY87JZ2B71_XR57EM

According to the passage, the author implies that foreign ecosystems have which potential effect on shorebirds? A. They can make a bird more vulnerable to predators. B. They can expose shorebirds to foreign toxins. C. They can diminish a bird's ability to navigate. D. They can lead to a reduction in the bird's weight. E. They can cause a bird to become separated from its flock.