八进制数字信号的传信率是3000bps,则其传码率为( )如果传信率不变，改为二进制数字信号传输，传码率为( )
A.2000b/s,3000B
B.3000b/s,2000B
C.3000b/s,3000B
D.1000b/s,3000B

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