This question already has an answer here:
I've added a suggestion on User Voice to consider the possibility of categorizing up to one answer per question as Canonical — i.e. worthy of being considered the consensus complete and accurate answer. A Canonical answer would have to include a link to an authoritative source, and at least 50% of voters would need to approve of it (as opposed to another answer to the same question or a "no possible canonical answer" option).
It's probable that many, if not most, questions would never have a Canonical answer. However, when one is possible and is provided, it should be a little more golden, and making it easier to find would be valuable for searching the site.