世界遗产保护范围，按照其总体规划分为（），分区进行保护．

世界遗产保护坚持（）的原则．

A．有效保护
B．统一管理
C．科学规划
D．永续利用

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What was the possible reason for the shuttle disaster?A．Columbia could not survive reentry.B．A block of foam damaged a wing.C．The aircraft disintegrated in the sky.D．The external tank was made of reinforced carbon. 点击查看答案