What is the purpose of an advance directive?

The purpose of an advance directive is to provide guidance for medical care when an individual is unable to communicate their preferences due to illness or incapacity. Advance directives are legal documents that allow individuals to specify their health care preferences and appoint a surrogate decision-maker. This ensures that their wishes regarding treatment and care are honored, even if they cannot express them at the time decisions need to be made.

In contrast, the other options do not align with the specific purpose of advance directives. Outlining financial decisions, naming beneficiaries for an estate, or establishing a trust pertain more to financial and legal planning rather than medical care decision-making. Therefore, option B stands out as the clear and relevant choice, as it directly relates to healthcare and the intent of advance directives to communicate a person's wishes in critical medical situations.