问题
单项选择题
数字证书是一条数字签名的消息，它通常用于________。
A．证明某个实体的公钥的有效性
B．证明某个实体的私钥的有效性
C．证明证书的签名的有效性
D．证明证书的发放者是真正的，而不是冒充的
答案
参考答案：A
解析：[知识点] 密钥管理[评析] 数字证书是一条数字签名的消息，它通常用于证明某个实体的公钥的有效性。
搜题请搜索小程序“爱下问搜题”
数字证书是一条数字签名的消息，它通常用于________。
A．证明某个实体的公钥的有效性
B．证明某个实体的私钥的有效性
C．证明证书的签名的有效性
D．证明证书的发放者是真正的，而不是冒充的
参考答案：A
解析：[知识点] 密钥管理[评析] 数字证书是一条数字签名的消息，它通常用于证明某个实体的公钥的有效性。
As darkness fell, hundreds of people in the Swiss village left their houses. They were staring（注视）forward at the mountain top in the distance. It was covered with ice and snow－beautiful and dangerous. The huge mountain is called Matterhorn. Mountain climbers had 40 the top through the southem route（路线）. But no one had ever dared to try a winter climbing up the northern side. But now one man was daring to try the 41 route. He was Walter Bonatti, a great mountain climber 42 Italy. For two days he had climbed. The village people had watched him anxiously（焦虑）. Now they were waiting to see his signal. If he planned to 43 the next day, he would light（点燃）a green signal（信号）. A red light would mean that he was turning back. A tiny green light 44 high on the mountain side. Bonatti was not giving up! The people 45 . The next day he continued his way upward. He was so lonely and so 46 ! But he would not give up. Again that night he lit the green light. In the morning, Bonatti 47 . He could not see the top；he knew he was 48 there. Though the climb was painful, he moved up. Bonatti had spent months 49 for the climb. Was the training enough? Did he have the strength and skill to climb to the top? He was finally at the top! News about his. 50 was radioed to the world. The trip down the southern route was easy. He was warmly welcomed in the village. He had done the “ 51 ” and would be well remembered as a climber of all time.
|