What is the purpose of using a time line when reading?
a. it enables you to place ideas into categories and subcategories.
b. it enables you to compare and contrast ideas
c. it enables you to locate minor details in text
d. it enables you to organize ideas into chronological order.

D, it enables you to organize ideas into chronological order

Explanation:

A timeline is a list or a display of events in chronological order, meaning in the order they appeared in a particular period of time or in a story.

There can be text timelines, number timelines or interactive ones.

A timeline is helpful while reading because it helps the reader to understand the subject better by seeing the main events written down separately. This way, the reader can refer back to them whenever he feels lost and fearing he can not follow the plot. Seeing the events in chronological order gives the reader a better point of orientation, especially if the book he is reading is a historical one with lots of dates and facts.

it might be b but i might be wrong