Historians base interpretations of past events on evidence they collect.
interviews with citizens.
opinions they have heard.
historical novels.

Evidence they collect.

Explanation:

Historians are scientists, social scientists, and they approach the study of history from a scientific point of view. For this reason, they approach the interpretation of past events with evidence. They only construct historical information if they have evidence to back their claims, whether it is a text, a testimony, or material evidence (archeological evidence).

the historians cited in the article all agree with one another about the cause of the civil war. despite coming from different backgrounds and cultures, the historians agree that slavery was the root cause of the civil war. the fact that all these historiansgenerally agree with one another makes their shared viewpoints more reliable and valid, especially because the historians have different backgrounds and all work for the well-respected institutions of howard university, clemson university, and the university of colorado.

because he had a big bear belly