document.write('<p>52.D【解析】D选项属于按洒水喷头的结构分类。</p><p><img src=\"http://www.alatiku.com/d/file/shiti/f516a2ccc3205e6ee21a34982a8de208.jpg\" alt=\"360截图20190427225104319.jpg\" width=\"302\" height=\"181\" /></p>');