Originally Posted by Sabertooth
I think the last word Brienne says is "Sapphires" fwiw. Not sure why, but that's the first thought that popped into my head.
I was pondering the last word, and signed up here just to comment on it...but someone took my answer already
I agree with sapphires. GRRM brings elements of the story back for effect, like when the red woman says "you know nothing jon snow."
It was a single word "sapphires" that saved her from being raped.
In the telling, I think it will fall out by her putting some puzzle pieces together using the idea of ransom (sapphires). She will figure out that someone is holding Sansa for her claim to Winterfell, and puzzles out that it is littlefinger.
Sapphires by itself will not save her life, she will follow it with a rush of words. maybe "sapphires" followed by narrated thought, then "she is with littlefinger" or something.
Any other word would be lacking that dramatic effect.