<select> 
  <optgroup label="Szwedzkie auta"> 
    <option value="volvo">Volvo</option> 
    <option value="saab">Saab</option> 
  </optgroup> 
  <optgroup label="Niemieckie auta"> 
    <option value="mercedes">Mercedes</option> 
    <option value="audi">Audi</option> 
  </optgroup> 
</select>

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