If C were true, that would mean that an innner class MUST extend ANY class or interface. This statement makes no sense at all. It MAY extend any class or interface, yes, but you can't say that it MUST. Only B is true.
"I'm not back." - Bill Harding, Twister
I’ve looked at a lot of different solutions, and in my humble opinion Aspose is the way to go. Here’s the link: http://aspose.com