Having hard time with my Ajax request in Jquery

I am trying to make an ajax request which would change the content of my select.

Here is my request :

    $(function() {
        $("#client").change(function() {
            type: 'GET',
            url: "jsonContacts.php",
            dataType: "json",
            data: {
                q: $("#client").val()
            },
            success: function(data) {
                document.form.contactClient.options.length=0;
                document.form.contactClient.options[0]=new Option("Test", "test", true, false);
                for(var i=0; i<data.length; i++) {
                }
            }               
        });
    });

My form is :

<FORM name='devis' method='POST' action='ajoutDevisScript.php' id='form' onsubmit="return validateForm()" >
<p>
    <label for="client">Client</label>
    <input type='text' id='client' name='client' required>
</p>
<p>
    <label for="contactClient">Contact client</label>
    <SELECT name="contactClient" id="contactClient">
    </SELECT>   
</p>
</form>

I would like that when the text of 'client' change, the request change the data of my SELECT but, my test Option isn't displayed at all.

Thanks!