how to disable option in select code example

Example 1: html non selectable option

<option disabled selected value> -- select an option -- </option>

Example 2: html select option disabled selected

<option selected disabled>Choose Tagging</option>

Example 3: disable other options in select except the selected

$("#lbCountries").click(function () {
     $("#lbCountires option").each(function (index) {
        if ($(this).is(':selected')) {
            $(this).prop('disabled', false);
         }
         else {
            $(this).prop('disabled', true);
         }
      });
  });