I tested this myself a while ago in the Test forum.
Have a look at this test thread I did;
http://forums.cnet.com/7723-6622_102-545362/how-to-select-best-answer/?tag=contentBody;threadListing
What you see and what I see will be different of course because I posted the original question, and you will just be a visitor. But if you read what I managed to do in the thread you will see you can 'change' which post answers your question.
You can't remove it if no-one has yet resolved the question, but if you have a selection of answers, you can change to any.
If you only have one "Answer" reply so far, or if none of them fits, then just post a note in the thread saying you made an error.
The world won't end. I think!
Mark
I was replying to a topic and it asked me if I wanted to leave it resolved or unresolved. I kept pressing unresolved and nothing happened. I didn't know how to get out of the screen and pressed "resolved" by accident. Is that able to be reversed? I still need help.

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