单选题
下面哪项是一种第2层协议,用于确保网络没有环路?()
题目答案
B
您的答案
答案解析
暂无解析
举一反三
Fatal error: Uncaught Error: Call to a member function query() on null in F:\duqu8.com\SaxueFrame\common\funarticle.php:16 Stack trace: #0 F:\duqu8.com\SaxueFrame\common\funarticle.php(51): formatContent('<p>\xE4\xB8\x8B\xE9\x9D\xA2\xE5\xAF\xB9\xE4\xBA\x8E...', Object(blockquestionlist)) #1 F:\duqu8.com\SaxueFrame\blocks\block_questionlist.php(107): formatQuestion(Array, Object(blockquestionlist)) #2 F:\duqu8.com\SaxueFrame\lib\template\template.php(640): blockquestionlist->setcontent(true) #3 F:\duqu8.com\SaxueFrame\data\compiled\templates\wap\question.detail.html.php(354): saxue_get_eloop(Array) #4 F:\duqu8.com\SaxueFrame\lib\template\template.php(329): include('F:\\duqu8.com\\Sa...') #5 F:\duqu8.com\SaxueWap\detail.php(81): saxuetpl->fetch('F:/duqu8.com/Sa...') #6 {main} thrown in F:\duqu8.com\SaxueFrame\common\funarticle.php on line 16