任何人都可以弄清楚为什么这段代码不起作用?我可以单击提交按钮并转到下一页而不选择任何内容。我希望仅当用户选择任何单选按钮时才允许用户转到下一页。谢谢
<script type='text/javascript' src='https://ajax.googleapis.com/ajax/libs/jquery/1.6.1/jquery.min.js'></script>
<script type='text/javascript' src='http://ajax.aspnetcdn.com/ajax/jquery.validate/1.11.1/jquery.validate.js'></script>
  <script>
  $.noConflict();
  $(document).ready(function(){
    $("#form1").validate();
  });
  </script>
 <form method="post"  action="/action" id="form1" class="styled" enctype="multipart/form-data">
  <label for="name">1. Choose Category</label><br />
<select class="required" id="cat1" name="category">
                <option>select Category</option>
                    <option class="required" value="10">Cars</option>
                    <option class="required" value="8">House</option>
                    <option class="required" value="11">Mobiles</option>
                    <option class="required" value="3">Bus</option>
                    <option class="required" value="6">Services</option>
          </select>
        <input type="submit" name="buttonSubmit" value="Next Step"   class="btn-submit img-swap"  id="submit"  />
</form>