How to Remove duplicate dropdown option elements with same value

How can I remove duplicate values -> drop down option elements?
I have the following HTML:

<option value="">All Servers</option>
<option value="com">http://smiles.com</option>
<option value="in">http://3smiles.com</option>
<option value="com">http://desk.com</option>
<option value="in">http://france24.com</option>

from the above I have to remove repeated values com and in, so my expected output should be like:

<option value="">All Servers</option>
<option value="com">http://smiles.com</option>
<option value="in">http://3smiles.com</option>

How to do it using jQuery?

Using .siblings() (to target sibling option elements), and Attribute Equals Selector [attr=""]

$(".select option").each(function() {
  $(this).siblings('[value="'+ this.value +'"]').remove();
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<select class="select">
  <option value="">All</option>
  <option value="com">.com 1</option>
  <option value="net">.net 1</option>
  <option value="com">.com 2</option> <!-- will be removed since value is duplicate -->
  <option value="net">.net 2</option> <!-- will be removed since value is duplicate -->
</select>

(works also for multiple .select on the same page)
^{I added a class .select to the <select> element to be more selector-specific}

How it works:
while options are accessed one by one (by .val()) - lookup for .sibling() options that have the same "[value='"+ this.value +"']" and .remove() them.

The correct solution will be is to not to allow the server to have duplicate values....

try

var map = {};
$('select option').each(function () {
    if (map[this.value]) {
        $(this).remove()
    }
    map[this.value] = true;
})

Demo: Fiddle