The following excerpt from when you reach me uses which literary technique to hint at future events:
if i’m not wrong, this is the story you wanted me to tell. and i didn’t know it yet, but it was also the end of my friendship with sal.
a. personification
b. theme
c. foreshadowing

well the answer is fore shadowing but im going to give you some examples to each answer.

Personification: is a figure of a speech in which a thing an idea or a animal is given human attributes. The non-human objects are portrayed in such a way that we feel they have the ability to act like human beings.

Theme: is a common thread or a main idea that is repeated throughout  literary work. The theme of a novel or story is the major message that organizes the entire work. The theme may be expressed overtly, but more often it must be uncovered by reading deeply through the work and analyzing the story's plot, characters and use of literary devices.

Foreshadowing:  is a literary device used to give a slight preview to something else that will happen later in a work. here is a example:if a author mentions a gun on a table then someone will invariably get shot before the story is over.

I hope these help you out. :)