Which of the following signifies a document that indicates a person's health care wishes in the event of a terminal illness?

The choice identifying advance directives is significant as it encompasses various documents that outline an individual's healthcare preferences in the event they are unable to communicate their wishes, particularly during terminal illness or incapacitation. Advance directives provide a legally recognized way for individuals to convey their choices regarding medical treatment and interventions, ensuring that their wishes are respected by healthcare providers and family members.

This option is broad and includes not only living wills but also healthcare powers of attorney, where individuals appoint someone to make decisions on their behalf. It is an essential tool for planning end-of-life care, allowing individuals to specify what treatments they do or do not want to receive. Thus, it directly pertains to the question of indicating health care wishes in the event of a terminal illness.

Other options like healthcare power of attorney represent a specific type of advance directive, which limits the scope of the answer. The guardian appointed order pertains to legal guardianship rather than direct healthcare wishes. The Oregon Death with Dignity Act is specific to physician-assisted dying within the state of Oregon and does not broadly cover the range of health care preferences indicated by advance directives.