图示对称结构中杆1与杆2的内力关系是（     ）

<img src、"http://zhejiang.ouchn.cn/pluginfile.php/61593/question/answer/385055/8/246788/7-04-A.png" alt="" width="83" height="21">

<img src、"http://zhejiang.ouchn.cn/pluginfile.php/61593/question/answer/385055/8/246789/7-04-B.png" alt="" width="68" height="21">

<img src、"http://zhejiang.ouchn.cn/pluginfile.php/61593/question/answer/385055/8/246790/7-04-C.png" alt="" width="84" height="21">

<img src、"http://zhejiang.ouchn.cn/pluginfile.php/61593/question/answer/385055/8/246791/7-04-D.png" alt="" width="60" height="21">