[jQuery] Everyone knows how to manipulate a SELECT with jQuery??

[etnas]

Hi!
Everyone knows how to manipulate the OPTIONS of a SELECT with jQuery??

I have, for example, this SELECT:

<select id="test">
  <option value="1">Option 1</option>
  <option value="2">Option 2</option>
  <option value="3">Option 3</option>
</select>

And I have 2 buttons on the document:

<input type="button" name="pre" id="pre" value="previous option" />
<input type="button" name="post" id="post" value="post option" />

Ok!; I need to change the selected option in the SELECT when I push
the 'pre' or the 'post' button and send the new value of the previous
or next option to a label:

<label id="the_previous_or_next_option_value"></label>

Thanks for your comments!