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当前学科：电台操作考试
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我国无线电频率划分表划分给业余业务使用的最高频带为241GHz-250GHz，属于无线电频谱的下列频带（波段）：（）
A . 极高频（毫米波）EHF
B . 超高频（厘米波）
C . 至高频（丝米波或亚毫米波）
D . 特高频（分米波）
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