Required: true rule or class='required' not working

Dear All,
Here is my link http://183.78.169.54/v3/addRoute.php where I can build dynamic combo boxes but the problem now is that I tried validating using both echo “<td><select class=‘required’ id=‘locationFrom’ name=‘locationFrom’ >”; and also like below. Unfortunately both does not work. Really lost how to validate combo boxes? Need help thank you.

function setupFormValidation(form) {
               // $(form).validate().resetForm();
                /*if ($('tbody tr', form).length < 2) {
                	  alert("Must Have End Destination Route");
                }*/
                
               /$('td:not(:first) select',form).each(function () {
                    $(this).rules('add', {required: true});
                });
                /*
                $('td:not(:first) select',form).each(function () {
                    $(this).rules('add', {required: true});
                });*/
               
            }