[{"FName":"Jane","LName":"Doe", "ID":"ABC123"},  {"FName":"Joe","LName":"Bloe", "ID":"XYZ456"} ]

Below is my AJAX call but I have not been able to display the JSON contents in a drop down list.  

1. var custNames= $("#Customers"); //Drop Down List ID
2.     $.ajax({
3.     url: 'http://localhost:32388/api/service',
4.     type: 'GET',
5.     dataType: 'json',
6.     contentType: 'application/json; charset=utf-8',                    
7.     success: function (data) {                                              
8.        custNames.append($('</option>', { value: -1, text: 'Select a customer' }));        
9.        $(data).each(function (index, item) {
10.              custNames.append($('</option>', { value:item.FName + ' ' + item.LName, text:item.FName + ' ' + LName}));
11.              custNames.append($('</option>', { value:item.ID, text:item.ID}));
12.        });
13.     }                
14. });

Please point out where I went wrong in my code, thanks.