multiple choice in c sharp

We can not give you the code here. You can still google to see if you can find similar example

But here is the pseudo code, go through it, you will find all the clues behind
1. Load the xml to XmlDocument. (namespace System.XML)
2. Parse the XML and get the answers in a IList or array string
3. Do a while loop on the collection object
4. Get each answer
5. Create a radio button dynamically and name it as radio_[counter] like radio_1, radio_2. This last number will be used to identify the answer when user checks a radio.
6. beside the radio, display the answer in a label.
7. There will be a button at the footer. Clicking the button will make a loop on radiobutton collection using forms.control
8. Get the checked radio button, parse the name of the radio button and get the last number.
9. Send the number to the database to get the answer. If matches, say "Right Answer", if no "Wrong Answer".

Try it yourself.
Best of luck.

cheers

As per your comments on xml, I tried to post the xml in comment.
Somehow the xml is not considered as valid text (probably due to security).

So, here is the sample xml with question, answer and correct flag.

<samplepaper>
<question id="1" description="What is the capital city of India?">
<answer id="1" description="Mumbai" flag="0" />
<answer id="2" description="Kolkata" flag="0" />
<answer id="3" description="New Delhi" flag="1" />
<answer id="4" description="Chennai" flag="0" />
</question>
<question id="1" description="XML can be parse using?">
<answer id="1" description="xmlparse" flag="0" />
<answer id="2" description="XmlDoc" flag="0" />
<answer id="3" description="XMLGrabber" flag="0" />
<answer id="4" description="XMLDocument" flag="1" />
</question>
</samplepaper>

Flag=1 is correct answer
Flag=0 is incorrect answer

cheers