Which document dictates how a deceased person's estate is to be distributed?

The correct choice, which is a will, is the legal document that outlines how a deceased person's estate will be distributed among heirs and beneficiaries. A will serves several important functions: it allows the testator (the person who writes the will) to specify their wishes regarding the distribution of their assets, appoint guardians for any minor children, and designate an executor to manage the estate's affairs after their passing. This process ensures that the individual’s intentions are honored and provides clear guidance to those managing the estate, minimizing potential disputes among survivors.

In contrast, a power of attorney is a legal instrument that grants another person the authority to act on someone's behalf during their lifetime, particularly in financial or health-related matters. It does not pertain to the distribution of an estate after death. A trust, while it can also dictate the distribution of assets, is a separate legal arrangement in which one party holds property for the benefit of another and typically requires active management. Lastly, a living will addresses healthcare decisions rather than asset distribution, outlining a person's wishes regarding medical treatment in the event they become unable to communicate those wishes themselves. Thus, a will is specifically designed to manage the posthumous division of an estate, making it the correct answer.