I'm saying that you can't know for sure so Agnosticism and morality is the most sensible out of any of them.
Agnosticism is nothing more then spiritual uncertianty at best, and an unwillingness to draw conclusions at worst.
Basically a refusal (for whatever reason) to subscribe to spiritual faith. Which is inconsistent (in a way) with the rest of human life, as faith is involved in most everything, in some fashion, and to different degrees.