How do I add additional information to a contribution page? PROFILE OPTION NOT WORKING
I had this problem last month and also posted my question on Stack Exchange - though I realize that most people who looked at my question and yours wouldn't think they were the same!  Check it out: Backbone isn&#39;t loading on Civi 4.6.11/WP 4.4.1

If you pull up your Developer Console (press F12 in your web browser when viewing this page, then check the "Console" tab, you should see the same errors I reference in my question.  If so, the answer is the same.

In less-technical terms - CiviCRM uses a pre-built package called "Backbone" to build the profiles on the page you're viewing.  Some Wordpress themes also use Backbone, and sometimes they conflict, which causes what you're seeing.  If you switch to a theme without this problem (for instance, the twentyfifteen theme), you should see the problem go away.

To fix my problem, you can use a different theme, or you can try to hack your theme.  I took the latter route; I created a child theme (there's lots of Wordpress documentation on that), and I overrode the objectionable code with my own code.