引起牙齿松动（病理性）的最主要疾病为（） A.地胎创伤 B.牙外_爱下问搜题

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问题单项选择题

引起牙齿松动（病理性）的最主要疾病为（）

A.地胎创伤

B.牙外伤

C.牙周炎

D.根尖周围炎

E.颌骨骨髓炎

答案

参考答案：C

选择题

把等质量的金属镁分别放在（1）氧气，（2）空气，（3）二氧化碳气体中完全燃烧，得到的固体质量分别是W₁、W₂、W₃，三者的大小关系是（）

A．W₁＞W₂＞W₃

B．W₁=W₂=W₃

C．W₃＞W₁＞W₂

D．W₃＞W₂＞W₁

完形填空

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