Final answer:
Investigators are recommended to keep all of the above: chronologies, to-do lists, and a separate file for key documents, along with maintaining a research log or annotated bibliography for organizational efficiency.
Step-by-step explanation:
When organizing documentary evidence, it is recommended that investigators keep all of the above: chronologies, to-do lists, and a separate file for key documents. Keeping a chronology helps to maintain a timeline of events which is crucial for understanding the sequence and context of the evidence. Maintaining a to-do list assists in keeping track of tasks to be conducted during the investigation and ensures that no aspect of the evidence collection is overlooked. Having a separate file for key documents allows investigators to quickly access critical pieces of evidence without wading through less crucial information. Furthermore, keeping a comprehensive research log or an Annotated Bibliography can serve as a centralized repository for all gathered information, streamlining the research process.