题目内容：
以下描述正确的是（）A.硅材料在自然界中非常丰富，存在天然的晶体硅
B.锗材料是稀有元素，得到高纯锗需要先制备锗精矿
C.制备金属锗最难去除的杂质是金属杂质
D.纯度太阳电池级多晶硅>电子级多晶硅
参考答案：
选择题：以下描述正确的是（）A.硅材料在自然界中非常丰富，存在天然的晶体硅
- 题目分类：中国大学MOOC慕课
- 题目类型：选择题
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