Before She Died, Lee Completed a Document Specifying Her Wishes

Before she died, Lee completed a document specifying her wishes to be taken off life support should she be in a position where she could not speak for herself and her recovery was all but impossible. Because the form did not give authority to anyone else to speak for her, Lee's document was MOST likely a(n) :

A) living will.
B) EEG.
C) survey of near-death experiences.
D) durable power of attorney.