Final answer:
The hunter's first responsibility after shooting an animal is to Ensure a humane kill, ensuring that the animal suffers as little as possible and is dispatched quickly.
Step-by-step explanation:
The first responsibility of the hunter once an animal has been shot is C) Ensure a humane kill. The key principle of ethical hunting is to make sure the animal is killed quickly and with as little suffering as possible. If the animal is not yet dead, the hunter must take immediate steps to put it down humanely. This also aligns with the traditional beliefs and practices of respecting the animal, as shown by the Rock Cree's hunting customs, where the animal's sacrifice is honored and no part of it is wasted. It is only after ensuring the animal has been killed humanely that the hunter can proceed to collect the trophy, leave the area, or call for assistance.