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当前学科:理化检验技术
题目:
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铜是人体必需的微量无素,以下正确的说法是()。
A . 任何一种铜盐都是无毒的
B . 金属铜无毒
C . 铜蒸气无毒
D . 铜盐毒性比金属铜大
E . 铜盐毒性比金属铜小
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