单选题船用雷达是建立在无线电波在任何两种媒质的边界面上必然产生反射，以及（）等基本传播特性的基础上的。A无线电波的传播是沿地表进行的B无线电波的传播是沿直线进行的C无线电波的传播速度是常数DB+C
单选题
船用雷达是建立在无线电波在任何两种媒质的边界面上必然产生反射，以及（）等基本传播特性的基础上的。
A
无线电波的传播是沿地表进行的
B
无线电波的传播是沿直线进行的
C
无线电波的传播速度是常数
D
B+C
参考解析
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