title: Select2 - Remove one option from multiple select box
body: <p>Say I have a select2 box like this:</p>
  
  <p><a href="https://i.stack.imgur.com/SrFoK.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/SrFoK.png" alt="Select2 Options"></a></p>
  
  <p>I want to remove the option '_Primary Care' (has option value 1), how do I go about doing this? I can clear all selected options by doing:</p>
  
  <pre><code>$('#categories-ids').val(null).trigger('change');
  </code></pre>
  
  <p>But I am not sure how to remove just one value.</p>