下列哪个命令是在当前主机的指定端口上启动远程对象注册服务程序
A． 组合框中，只有一个条目是可见的
B． 组合框不提供多重选定的功能
C． 组合框没有MnltiSelect属性的设置
D． 以上说法均正确
参考答案：D
解析：本题中选项A) ，B) ，D) 都是数据库表的特点，在自由表中无法实现这些功能，且只能建立候选索引、惟一索引和普通索引3种索引类型。
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| A piece of advice that I often receive is "as long as you do your best". I believe that this is good advice _1__ it tells me that they trust my __2__ and will respect my decisions, even if they are the wrong ones. This helps to take __3__ off me when I am going to school because I don't have to __4__ certain standards and try to __5__ goals that are unattainable. __6__, I can just worry about doing the best I can. It is possible that I may have a __7__ that is not the highest paying or the most respectable. But as long as I do the job to the best of my ability, I will feel like I have accomplished __8__. This is good because many kids have to live up to expectations that they can't attain, or do something that they don't really __9__ in order to make their parents 10 . The 11 with saying "as long as you do your best" is that when I know I could have done a better job, I have a sort of 12 feeling. I hate it 13 I get a low mark 14 fail in something and my parents say "as long as you tried your hardest". However, when I know I did the work as well as I could but it isn't a good mark, I don't worry about it 15 some people might. In 16 , the piece of advice is basically a good one, and often it 17 me motivated in the things I do. It also 18 me that my parents will support most of my decisions and treat me like a 19 person. I will probably 20 the advice "as long as you do your best" to my children. | ||||
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