【单选题】
正面和水平投影图所对应的侧面投影图为 。<img src="https://file.icve.com.cn/doc_public2/963/120/F0C1E39E534CDD6CEFEC0C0481C5E3D1.png" title="1.png" alt="1.png"/>
①
<img src=http://222.173.11.71/doc_public/b@D4BB62899709BE2F45F414C28A4CA9A7.png title=2.png alt=2.png/>
②
<img src=http://222.173.11.71/doc_public/b@D26AC752421CD577BAB086C3FDDDFA77.png title=3.png alt=3.png/>
③
<img src=http://222.173.11.71/doc_public/b@41023E220058FAAA5E536AE1226629A8.png title=4.png alt=4.png/>
④
<img src=http://222.173.11.71/doc_public/b@14215B63E40DF13F895F5CB38760F767.png title=5.png alt=5.png/>