Why should historians avoid oversymplfying

The correct option is "A- Oversimplifications often ignore complex or condradictory evidence."

Historical sources constitute the raw material of History. They include all the documents, testimonies or objects that transmit us significant information regarding the events that have taken place, especially in the past. Within them, and considering the value that others also have, the written sources are the basic support to build history.

The historian works historical sources ("interrogates and contrasts") to obtain as much information from them as possible. It must also attend to its variety, making an adequate selection of them. In a general sense, historical sources are of two types: primary and secondary.