Which document allows another person to decide on health care matters if someone becomes incapacitated?

The Durable Power of Attorney is the correct choice because it specifically grants a designated individual the authority to make health care decisions on behalf of another person who is unable to do so due to incapacitation. This document is legally binding and provides the appointed person, often referred to as an agent or proxy, the ability to act in the best interest of the individual, ensuring that their health care preferences are followed.

While a Living Will outlines a person's wishes regarding medical treatment in situations where they may not be able to communicate those wishes (typically focused on end-of-life care), it does not appoint a person to make decisions. A Health Care Directive encompasses both a Living Will and a Durable Power of Attorney; however, it does not specifically emphasize the delegation of decision-making authority to an agent. An End-of-Life Agreement relates to discussions about care preferences but lacks the legal power granted by a Durable Power of Attorney. Thus, the Durable Power of Attorney is the most appropriate document for appointing someone to make health care decisions in case of incapacitation.