Question and Answer Form in asp.net c#

Question

Hi,

    I'm creating a website where users can post their questions and other users can answer to their questions.

Now the problem is that i'm looking for something like a user replied on a question and again i want to reply to that person who replies to question.

 

Architecture:

Question

   Answer to Question

      Reply to Answer

 

i hope you're clear what i'm looking for.. 

 

Please have a look at the image below so you can get a better idea:

http://oi58.tinypic.com/w8kjt3.jpg

 

 

Thanks