How might organizing U. S. history using only this historian's periodization be a problem for a student of history?

because it helps them organize when important events happen and to compare different periods in history. How do historians use eras as a tool to study the past? this helps historians to organize where things happened inthe past.

the answer would be a i think?

the answer is a. laws were enacted in the aftermath of the plot to make it harder to free slaves,increasing sectionalism