As a hypothetical example, let's say I post a question; "My tyre keeps going flat. I've checked there's no nails in it. What could be wrong ?"
I'll get a couple of replies, such as "Check the valve isn't leaking" or "Check there aren't evil pixies stealing the air while you're not looking".
Then I'll get one; "Check there isn't a nail in the tyre".
It seems a bit rude to say I already mentioned that in the first post and make them look foolish, when they are obviously just trying to be helpful.
It also seems a bit rude to ignore them and not thank them for their effort.
What is the correct response ?