These choices do not cover the possibilities very well. In particular, an answer might be perfectly relevant (on topic) but be wrong or debatable.
I would hesitate to add too many rating categories, but I think that having two categories would be better than at present: one for quality, the other for relevance.
This could be expressed as one rating with four choices: relevant and good, relevant but questionable, irrelevant but interesting anyway, and irrelevant period. Maybe a fifth choice for offensive (but there already exists a method to report those).
Good Answers: