JSFiddle - React, Tailwind, and code Playground

HTML

<select id="1">
  <option value="volvo">Volvo</option>
  <option value="saab">Saab</option>
  <option value="mercedes">Mercedes</option>
</select>

<select id="2">
  <option value="volvo">Volvo</option>
  <option value="saab">Saab</option>
  <option value="mercedes">Mercedes</option>
</select>

JavaScript

$("select").change(function()
                   {

        $("select option").attr("disabled",""); //enable everything
        DisableOptions(); //disable selected values

                   });


function DisableOptions()
{
    var arr=[];
      $("select option:selected").each(function()
              {
                  arr.push($(this).val());
              });

    $("select option").filter(function()
        {
             
              return $.inArray($(this).val(),arr)>-1;
   }).attr("disabled","disabled");   

}