Where does the speech occur?
The speech occurs（）.

A．Playing chess.B．Discussing some political issues.C．Attending a party.D．Writing some letters.

A.Playing
B.
B．Discussing
C.
C．Attending
D.
D．Writing
E.

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在现代通信技术中，数字信号可以进行数字传输，也可以进行模拟传输。实现数字信号转变成模拟信号的技术称为A．调制 B．解调 C．编码 D．解码 点击查看答案