When I'm flagging a comment, which flag reason should I use?
Per this MSE post:
When should I flag a comment?
You must specify a reason for each comment flag. The dialog offers a few pre-filled reasons that cover most common cases:
It contains harassment, bigotry, or abuse.
The comment attacks a person or group.
It's unfriendly or unkind.
The comment is rude or condescending.
It's no longer needed.
This comment is outdated, conversational or not relevant to the post.
A problem not listed above. Try to be as specific as possible.
See also When should comments be deleted?.