Get List Item ID when a SharePoint choice column changes

<script type="text/javascript" src="https://code.jquery.com/jquery-1.12.4.js"></script>
<script type="text/javascript">

$(document).ready(function() {  
$("select[title='ChooseCountry']").change(function() {  
    var stage = $("select[title='ChooseCountry']").val();    
    var itemID = getParameterByName('ID');        
    var URL = $("input[id^='Asset_x0020_Link']").val();
    alert(ID);

});
});

function getParameterByName(name) {
    name = name.replace(/[\[]/, "\\[").replace(/[\]]/, "\\]");
    var regex = new RegExp("[\\?&]" + name + "=([^&#]*)"),
        results = regex.exec(location.search);
    return results === null ? "" : decodeURIComponent(results[1].replace(/\+/g, " "));
}

</script>