Which term best describes a legal document granting someone authority to act on another's behalf?

The term that best describes a legal document granting someone authority to act on another's behalf is a Power of Attorney. This document gives a designated person the legal authority to make decisions and take actions on behalf of another individual, particularly in matters related to finances, healthcare, or legal affairs. The scope of authority granted can vary, from broad powers to specific instructions, depending on the wishes of the person granting authority, known as the principal.

The other terms, while related to legal contexts, do not specifically define a document that grants such authority. Legal Representation typically refers to an attorney's role in a legal matter rather than a formal document. Statutory Authority Document is not a standard term and does not describe a power or authority context. Authorized Consent Form usually pertains to consent given for specific actions, such as medical treatment, rather than the broader authority to act on another's behalf.