This is strange

[Tonata]

Hi all, I am coding an application that conducts student tests and exams online. I save the answers to the database individuallly, so for each question and answer I have a Save button. When this button is clicked, the system connects to the DB with ajax and saves the answer. The problem I have now is this works in Firefox but not in Internet explorer, can anybody please explain to me why. Below is my code

My function

	function updateAnswer(questionNum) {
       
	   var answer = $('#answer_'+questionNum+':checked').val();
        if (answer==undefined){
			answer  = $('#answer_'+questionNum+'').val();
		}
		var questionNumber = $('#questionNumber_'+questionNum+'').val();
		var test = $('#testId').val();
		var student = $('#student').val();
			
			$.ajax({
				type: "POST",
				url: "ajax.updateAnswer.php?student="+student+"&questionNumber="+questionNumber+"&answer="+answer+"&test="+test,
				success: function(result){
					if (result == 'KO') {
						alert('Question could not be updated');
					} else {
						$('#update_'+questionNum+'').removeAttr('disabled', 'disabled');
					}
				}
			});

    };

Update answer is called onclick of the Update button, in the function I pass the id of the question as parameter.