In October I asked a question, How do I make apps in my optional package run using the virtualized file system/registry of the main package?
In December someone gave an answer to it. In the meantime, my work had made changes to our plans which made the question irrelevant, and I had forgotten about the question. So when I was reminded of it, I wanted to close it or mark it somehow so that no one else would put a lot of effort into answering it.
But your list of "reasons to close a question" doesn't include an option that says "I don't care about this question any more", so I can't close it without lying about the reason. I would like to take a moment to say that it's really stupid that you have a hardcoded set of reasons for closing a question with no free-text "other" option, because people will always come up with edge cases that haven't been anticipated by the person coming up with the list.
I just deleted the question because I know of no other means of disavowing it.