Use this for latest version from google (although I personally don't recommend you to use latest version):
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
Why does it point to 1.9.1?
The latest version of jQuery may not be compatible with the existing plugins/code on the site. Version updating should be an intentional decision. The latest version has a very short max-age=3600 compares to the specific version of max-age=31536000, which means you won't get the benefits of long-term caching.
So, Google doesn't waste its resources unnecessarily. You'll need to manually upgrade the URL to the latest.