Why is differentiating between the past, present, and future an important element of chronological thinking

It is considered as an important element of chronological thinking when differentiating between past, present, and future because it is easier to locate or detect the events in a temporal order, it is possible for the students to investigate, study, and evaluate relationships among those events or to explain the historical principle that everything has a cause.

cuban communists pressured the soviet union to place missiles in cuba.

your answer would be (a)