哪项技术允许用户验证网络身份并信任从互联网上下载的代码? A.
非对称密钥算法 B.
数字签名 C.
加密 D.
散列算法

A． B． C． D．

单项选择题

A．
B．
C．
D．

听力原文：Can you see a space anywhere? This is the trouble ...

未知题型听力原文：Can you see a space anywhere? This is the trouble with coming into work latE.Well, I'm just going to have to use the director's placE.I think she's away, anyway.
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简单管道是指管道直径不变切无分支的管道。

判断题简单管道是指管道直径不变切无分支的管道。