Chronological order is useful when a writer wants to readers understand
a. the points of view of several characters.
b. any events that happened previously.
c. details and connections about the story’s events.
d how two different elements compare to each other.

The answer is C, because chronological order means in a sequence of events.

The reason an author includes the use of chronological order is to help the reader to understand how something came to be usually. There are times when the author foreshadows the events, but either way the author wants to help the reader understand the sequence of events to catch the reader up to a certain point in a story.

Hope this helps.