The correct answer is A. Organizing Roman history into 3 main eras
Explanation:
Periodization in history refers to the process of studying and categorizing events of the past in to block of time. This process is aimed at facilitating the analysis of historical events and understanding the causes of specific historical processes. Additionally, periodization is useful as blocks of time are organized according to relatively common characteristics. Considering periodization is applied when categorizing or organizing events of the past, it can be applied to Roman history which result could be 3 main eras with common historical features. Thus, periodization is useful in the case of organizing Roman History.
Advantage: They were fighting on their home country. (they didn't have to travel overseas) Britain was fighting France at the same time as they were fighting the US
Disadvantage: They didn't have a trained army. They didn't have much $.