（ ）是控制通信过程的规则。
举一反三
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- <p style="text-indent:19px<strong><span style="font-family: 宋体;font-size: 19px<span style="font-family:宋体在下列四种说法中，选择一种正确的答案。</span> <span style="font-family:宋体（</span></span></strong><strong><span style="font-family: 宋体;font-size: 19px ）</span></strong><strong> </strong>https://image.zhihuishu.com/zhs/onlineexam/ueditor/201910/b77fd28130934107bbf54f03e2772cc0.png<strong><span style="font-family: 宋体;font-size: 19px </span></strong><br>
- 以下html标签嵌套正确的是（） A: ＜span＞＜b＞更多＜/b＞＜/span＞ B: ＜span＞＜strong＞更多＜/strong＞＜/span＞ C: ＜span＞＜strong＞更多＜/span＞＜/strong＞ D: ＜img＞＜/img＞
- <p style="margin-left:67px<strong><span style="font-family: 宋体;font-size: 19px<span style="font-family:宋体在下列四种说法中，选择一种正确的答案。</span> <span style="font-family:宋体（</span></span></strong><strong><span style="font-family: 宋体;font-size: 19px ）</span></strong>https://image.zhihuishu.com/zhs/onlineexam/ueditor/201910/07949bcb17164c52ac3c062ce83fe44b.png
- <strong><span style="font-family: 宋体;font-size: 19px<span style="font-family:宋体圆盘上四个小孔需标注定位尺寸，其定位尺寸是（</span> </span></strong><strong><span style="font-family: 宋体;font-size: 19px </span></strong><strong><span style="font-family: 宋体;font-size: 19px </span></strong><strong><span style="font-family: 宋体;font-size: 19px<span style="font-family:宋体）</span></span></strong><strong><span style="font-family: 宋体;font-size: 19px https://image.zhihuishu.com/zhs/onlineexam/ueditor/201910/7325982780f44a89af1ba0f39ab8d237.png</span></strong>