Final answer:
The most respectful way to present a pet to an owner after euthanasia is in a waterproof body bag, offering a clean and dignified approach while providing support to the grieving owner.
Step-by-step explanation:
When a pet has been euthanized, it is a best practice for veterinary professionals to present the pet to the owner with dignity and respect. The most appropriate and respectful option from the list provided would be (C) Waterproof body bag. This allows for a clean, dignified, and discreet way to handle the pet. The bag should be labeled appropriately, and the pet should be placed gently within it. It is also important that the staff convey their condolences and support to the grieving owner, and handle the situation with the utmost sensitivity.