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【单选题】
在 OSI 模型中上下两个层次的关系用( )来表示。A.
发送与接收
B.
请求与应答
C.
提供服务与使用服
D.
协议与规定
拍照语音搜题，微信中搜索"皮皮学"使用
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皮皮学刷刷变学霸
举一反三
【单选题】The decline in moral standards—which has long concerned social analysts—has at last captured the attention of average Americans. And Jean Bethke Elshtain, for one, is glad. The fact that ordinary citi...
A.
have adapted to a new set of moral standards
B.
are longing for the return of the good old days
C.
have realized the importance of material things
D.
are awakening to the lowering of their moral standards