Final answer:
The right that appoints a healthcare representative is the power of attorney, which allows a designated individual to make critical healthcare decisions for a patient who is no longer able to do so.
Step-by-step explanation:
The patient right that appoints a healthcare representative is c. Power of attorney. This is a legal document that enables a person to designate another individual, often referred to as a health care proxy or agent, to make medical decisions on their behalf should they become incapable of making such decisions themselves. This includes decisions about medical treatments, health care providers, and living arrangements, among other health-related concerns. The principle of autonomy is a cornerstone in healthcare which allows patients to exercise agency in determining their course of treatment and care. Additionally, living wills are also pertinent as they detail specific medical interventions an individual desires or declines in advance, particularly at the end of life or in situations where the individual can no longer communicate their wishes.