Adding a clear option to the drop down list using javascript
<p>I have a drop down similar to this:</p>

<pre><code>  &lt;select&gt;
     &lt;option value=" " id="invisible" style="display:none;"&gt;&lt;/option&gt;
     &lt;option value="0"&gt;one&lt;/option&gt;
     &lt;option value="1"&gt;two&lt;/option&gt;
     &lt;option value="2"&gt;three&lt;/option&gt;
     &lt;option value=""&gt;clear&lt;/option&gt;
  &lt;/select&gt;
</code></pre>

<p>When I press 'clear' option, the drop down list should show nothing (even 'clear') but not delete any options inside i.e. nothing should show on the dropdown list until it is clicked.</p>

<p>Please advise.</p>
