第5题: [单项选择]Passage Two Questions 30 to 32 are based on the passage you have just heard. A. To forbid grazing on marginal lands. B. To plant more trees on marginal lands. C. To establish good ground cover. D. To graze animals rotationally. 参考答案:D 答案解析:[听力原文] Q: According to the speaker, how to reduce the damage on marginal lands from overgrazing <