Laravel php dynamic dropdown list

I would like to create a dynamic dropdown list dependent based on module code. The dependent dropdown list should show the available class for selected modules. There are 2 tables one is called modules and mupp_classes. the Models are connected to a controller for each table. module_code is the FK for mupp_classes. The column for the classes is called name in mupp_classes below are the code which I currently have.

my javascript

<script>
$('#module_code').on('change', function(e){
    console.log(e);
    var module_code = e.target.value;

    $.get('admin.ajaxFunction' + module_code, function(data) {
        console.log(data);
        $('#mupp_classes-name').empty();
        $.each(data, function(index,subCatObj){
            $('#mupp_classes-name').append(''+subCatObj.name+'');
        });
    });
});

my route

 Route::get('ajax-state','ClassController@ajaxFuction')->name('ajaxFunction');

My controller

public function ajaxFunction()
{

    $code = Input::get('module_code');
    $subcategories = mupp_Class::where('module_code','=',$code)->get();
    return $subcategories;

 }

my view

 <div class="form-group">
                <label for="modulecode">Module code</label>
                <select id="module_code" class="form-control" name="module_code">
                    <option value="">Select Module Code</option>
                    @foreach ($moduleslist as $module)
                        <option value="">
                            </option>
                    @endforeach
                </select>
            </div>

            <div class="form-group">
                <label for="mupp_classes-name">Module Class</label>
                <select id="mupp_classes-name" class="form-control input-sm"
                        name="mupp_classes-name">
                    <option value=""></option>

                </select>
            </div>

via Wei Jun