生态平衡是一种[]A．动态平衡B．绝对平衡C．永久的平衡D．动植物数量相等-八年级生物

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• 下列关于生态平衡的叙述，正确的是[]A．生态系统一般不会出现平衡状态B．生态平衡意味着生态系统中各种生物的数量恒定不变C．破坏生态平衡的主要原因是恶劣的自然条件D．生态系统-八年级生物
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