<select id="select1">  <optgroup label="Swedish Cars">    <option value ="http://www.mamicode.com/volvo">Volvo</option>    <option value ="http://www.mamicode.com/saab">Saab</option>  </optgroup>  <optgroup label="German Cars">    <option value ="http://www.mamicode.com/mercedes">Mercedes</option>    <option value ="http://www.mamicode.com/audi">Audi</option>  </optgroup></select>  jQuery("#select1  option:selected").text();