I would agree with you on internal!!
Answer:
the overall mood.
The tone of a story is how the author shows the general attitude in the story. So if the story seems sad through the words, you can assume the rest of the story will be as well.
Think of it as a horror movie. Weird or scary things happen in the beginning, and that general tone/theme will continue throughout.
Romeo falls in love with juliet by sight and sneaks up on her, and gets caught
