Dynamicaly choose select option value as parameter

Hi, i am fighting few days with one problem to get from drop down the option value on send button

Still send me as parameter first option... no matter if i choose other one. for input fields works this great but i stack on drop-down... tried xyz stack-overflow possibilities.... but without any solution...

Please how to solve that i can dynamicaly send dropdown value to parameter ?

                    <select id="getSearchModule" name="m"
                        <option value="property" >Properties</option>
                        <option value="todo" >Todos</option>
                        <option value="landlord" >Landlords</option>
                        <option value="offer" >Offers</option>
                        <option value="opportunity" >Opportunities</option>
                    </select>

ajax: {
     url: '{{ path('test_service') }}',
     type: 'POST',
     async: true,
     data: function ( d ) { d.getSearchModule = $('#getSearchModule').val(); }
}

Thank you