D. Chronological thinking
Historians tend to form periods of time, often reflected in timelines, where they include a criteria for making such choices, as it is not just an arbitrary issue.
Here is where the importance of chronological reasoning is a skill that integrates secondary skills: namely:
historical causation (finding causes and common circumstances or origins: events leading to a war), noticing
patterns of continuity and change over time (for example, distinguishing if something is a sui generis event, or if it shows continuity from previous historical processes) we can say something is Post-Westfalia, neo... classic, etc.
periodization, (if something is happening in certain cycles or periods). Golden age, Classical age, etc..
