Final answer:
The AAHA, not listed in the options, provides voluntary accreditation for veterinary hospitals; of the given choices, none directly offer accreditation, with the AVMA being closest as a veterinary association.
Step-by-step explanation:
The organization that offers voluntary accreditation for veterinary hospitals is the AAHA, which stands for the American Animal Hospital Association, not directly listed as an option in your question. However, among the options provided, the closest is the AVMA (American Veterinary Medical Association), which is a professional organization associated with veterinary medicine but does not offer accreditation for hospitals. The other options, such as FDA, WHO, and OSHA, are involved in regulation and workplace safety but do not provide accreditation for veterinary hospitals.