(单选题)单选6.图示阶梯形杆总变形为( )<img src="https://zk.995w.com/lqwvjeImg/8f/8f4d85fc6352b0d1a88cedc2f7e5ba93.png"style="width:417px;height:168px;">(本题3.0分)<br>·0<br>·<img src="https://zk.995w.com/lqwvjeImg/3f/3fa13e138764d10585d5e2a50efe5ede.png"style="width:78px;height:54px;"><br>·<img src="https://zk.995w.com/lqwvjeImg/dd/dd57c2fb202a7bb48a14581aeab2d363.png"style="width:73px;height:54px;"><br>·<img src="https://zk.995w.com/lqwvjeImg/b4/b4feec960573252e07734d3d053c61f1.png"style="width:81px;height:54px;">