Try it Live - HTML optgroup tag

​x
 
<!DOCTYPE html>
<html>
  <body>
    <select>
      <optgroup label="Select country">
        <option value="india">India</option>
        <option value="usa">USA</option>
        <option value="japan">Japan</option>
        <option value="canada">Canada</option>
        <option value="australia">Australia</option>
        <option value="brazil">Brazil</option>
      </optgroup>
    </select>
  </body>
</html>
​