What I want is to show a <tr> when a specific value of <select> <option> is selected.

I got this code so far:

2. <script>
3. (document).ready(function(){
4.   $(form select option[value='specified_range']).focus(){
5.     $(".appel").show();
6.   }else{
7.     $(".appel").hide();
8.   }
9. );
10. </script>
11. 
    
13. <select name="walk_mode" id="walk_mode">
14. <option value="freeroam">Lopen</option>
15. <option value="stand">Stilstaan</option>
16. <option  value="specified_range">Beperkt Lopen</option></select>

When I click the last option it should display a <tr> with class="appel"

If one of the first two options is selected it should do nothing.

I'm really new to jQuery but this is something I cant get to work.