JSFiddle - React, Tailwind, and code Playground
HTML
<select id="first">
<option value="none">None</option>
<option value="one">Toyota</option>
<option value="two">Nissan</option>
<option value="three">Dodge</option>
</select>
<select id="second">
<option value="none">None</option>
<option value="one">Toyota</option>
<option value="two">Nissan</option>
<option value="three">Dodge</option>
</select>
JavaScript
$("#first").change(function() {
if($("#first").val() != "none") {
$("#second option[value!="+$("#first").val()+"]").show();
$("#second option[value="+$("#first").val()+"]").hide();
} else {
$("#second option[value!="+$("#first").val()+"]").show();
}
$("#second").val('none');
});
$("#second").change(function() {
if($("#second").val() != "none") {
$("#first option[value!="+$("#second").val()+"]").show();
$("#first option[value="+$("#second").val()+"]").hide();
} else {
$("#first option[value!="+$("#second").val()+"]").show();
}
$("#first").val('none');
});