题干

下列关于草原生态系统的表述正确的是()
①生物多样性是其自动调节能力的基础 ②其抵抗力稳定性要比森林生态系统低
③其恢复力稳定性要比苔原生态系统低 ④进入该生态系统的能量最终以热能形式散失
⑤跳羚擅长使用“小牛跳跃”的特殊方式吓跑追赶它们的动物,这属于行为信息
⑥草原生态系统的信息传递是其物质循环和能量流动正常进行的保障
⑦广阔的草原能激发艺术创作灵感,属于其间接价值

A:②③⑤⑥⑦

B:①②⑤⑦

C:②④⑤⑥

D:②④⑤⑥⑦

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C

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    One of the main challenges facing many countries is how to maintain their identity in the face of globalization and the growing multi-language trend. "One of the main reasons for economic failure in many African countries is the fact that, with a few important exceptions, mother-tongue education is not practiced in any of the independent African states." said Neville Alexander, Director of the Project for the Study of Alternative Education in South Africa at the University of Cape Town.

    In response to the spread of English and the increased multi-language trends arising from immigration, many countries have introduced language laws in the last decade. In some, the use of languages other than the national language is banned in public spaces such as advertising posters. One of the first such legal provisions(规定) was the 1994 "Toubon law" in France, and the idea has been copied in many countries since then. Such efforts to govern language use are often considered as futile by language experts, who are well aware of the difficulty in controlling fashions in speech and know from research that language switching among bilinguals is a natural process.

    It is especially difficult for native speakers of English to understand the desire to maintain the "purity" of a language by law. Since the time of Shakespeare, English has continually absorbed foreign words into its own language. English is one of the most mixed and rapidly changing languages in the world, but that has not been a barrier to acquiring superiority and power. Another reason for the failure of many native English speakers to understand the role of the state regulation is that it has never been the Anglo-Saxon way of doing things. English has never had a state-controlled authority for the language, similar, for example, to the Academic Francaise in France.

    The need to protect national languages is, for most western Europeans, a recent phenomenon—especially the need to ensure that English does not unnecessarily take over too many fields. Public communication, education and new ways of communication promoted by technology, may be key fields to defend.