Edit in JSFiddle

(function ($) {
    $('#remove_multiple').on('click', function () {

        var multiple_text_to_remove = $('#languages4').val();

        $(multiple_text_to_remove).each(function (k, v) {
            $("#languages4")
                .find("option[value='" + v + "']")
                .remove();
        });


    });
})(jQuery);

<div class="code_example">
    <select name="languages" id="languages4" multiple>
        <option value="c">C</option>
        <option value="c++">C++</option>
        <option value="php">PHP</option>
        <option value="perl">PERL</option>
        <option value="ruby">RUBY</option>
        <option value="python">PYTHON</option>
        <option value="go">GO</option>
    </select>
    <br/>
    <input type="button" class="btn btn-danger" id="remove_multiple" value="Remove Multiple" />
</div>