It doesn't matter that much which of these reasons you choose if the comment is flag-worthy. Having two separate CoC based flag reasons merely makes it clearer what kind of behaviour is not welcome on Stack Exchange: clearly, attacks and harassment are absolutely unacceptable. But condescending behaviour has no place here as well, even when it doesn't rise to the intensity of abusive behaviour.
Selecting the more suitable flag reason does make it easier for mods to confirm or reject the flag. E.g. it is clearly wrong to flag a comment as abusive when it merely asks “What do the docs say?”. But it could merit a flag as “unfriendly”, depending on context. Note that if context is very important for why a comment was flagged, then explaining this with a custom flag reason is often the better choice.