Out of that list there I would say in this order:

bear
cougar
shark
wolf

I have no stats to prove this, and actually I have no idea about sharks. Cougar attacks don't always end in a death either, they are often killed and the attacked person has wounds to heal from.

Bears are definitely the main one around here. I meet up with piles of bears each summer and have not had an incident yet, so those too are rare given the number of encounters.