Collapse and Expand Section in Word 2010 Based on Radio Button Choice

I searched www and Stack Overflow but couldn't find the answer.

I am trying to create expandable and collapsible sections in Word 2010 based on radio button choice. So if you click radio button A, section 1 appears. If you click radio button B, section 1 disappears. Sounds simple, but I can't find resolution.

How do I register these radio buttons and correlated them to section 1? I understand that I have to bookmark my section, register radio buttons and then create a macro that unifies all of the above, but then I get lost.

Thank you very much.