GRE Reading Comprehension: JiJing 352-GRE阅读机经352篇 - 66Z407675TQDQK0EJ

The passage implies which of the following about the problems ragwort poses to dairy farmers? A. Milk produced by cows that eat ragwort causes illness in humans who drink it. B. Ragwort can supplant the plants normally eaten by cattle. C. Cattle, unlike sheep, are unable to differentiate between ragwort and healthy grazing.