第10题: [单项选择]Those were the graduate assistants ______ to do the research work in the lab. A. to whom it was their responsibility B. whose responsibility there was C. whose responsibility was D. of whom with the responsibility 参考答案:C 答案解析:语法结构题。此题考查属格关系代词引导的定语从句，[A]、[D]项应先排除；[B]项从句的谓语为there be结构，讲不通；因此只有[C]项为正确答案。
第14题: [单项选择]使用公钥加密时，密钥分发的两个不同方面是( )。 A. 密钥交换和公钥更新 B. 公钥分发和私钥分发 C. 公钥分发和用公钥加密分发保密密钥 D. 密钥登记和公钥分发 参考答案:C 答案解析:[解析] 密钥管理的重要内容是解决密钥的分发问题。使用公钥加密时，密钥分发有两个不同的方面：公钥分发和用公钥加密分发保密密钥。
