SQL语言的REVOKE语句实现下列哪一种数据控制功能A．可靠性控制 B．并发性控制
题型：单项选择题
问题：
SQL语言的REVOKE语句实现下列哪一种数据控制功能
A．可靠性控制
B．并发性控制
C．安全性控制
D．完整性控制
题型：单项选择题
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 1. ______ It has around 3 billion fans - nearly half the world's population! And about 300 million people play this game. That's 4 percent of the world' s population! 2. ______ Many people in old days played early forms (形式) of this modern game. Cu ju (蹴鞠), a ball-kicking game in China, was reported as early as 2,500 B.C. Around the same time in Greece, people were also playing a similar ball game without using their hands. But modern soccer didn't become official (官方的) until 1863. An Englishman called Cobb Morley introduced the idea of a soccer association (联盟). 3. _______ From then on, other associations in the countries were set up. They came together-to make up the FIFA, which organizes the World Cup. It's not easy to tell what makes soccer so popular. 4. ______ Soccer needs only two feet and a ball. This makes it a sport that developing countries can easily play. Some of the sport' s best players come from these poor nations. 5. _____ The sport's no-hands rule makes beautiful dance-like movements on the field. What's more, this sport excites the heart. Teams might score only a few times each match, so matches can turn around suddenly. No one knows who will win at the next World Cup. But one thing is certain: The world will be watching.
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