Is there a reason to use XML???
XML isn't, by nature, "interactive". So I don't understand how you would publish a quiz using XML.
I guess you could publish a web service that would get questions and then accept answers to those questions and give a score. And of course you could use SOAP for the web service and SOAP is based on XML.
But depending on what you really need to do, that may be WAY overkill.
Certainly, if *YOUR* site will be providing the quizzes to browsers, I see no reason at all to involve XML. Oh, not that you can't do it. But why?
Reading PDF isn't the easiest thing in the world. Period. You will need to find some component capable of doing so, using whatever technology you intend to implement this with.
Speaking of which, what technology *ARE* you proposing to use??? JSP? PHP? ASP or ASP.NET? CF? What?