Which of the following types of filing systems requires a cross-reference file?

A numeric filing system organizes files based on numbers rather than names or dates, which can lead to difficulties in locating a specific file if you only remember some of the details related to that file. To address this challenge, a cross-reference file is necessary. This cross-reference file provides an additional layer of organization that helps users find files associated with a specific number by linking that number to relevant information, such as the name of the patient or the type of document. Thus, the use of a cross-reference file enhances efficiency and ensures that the correct documents are retrieved without confusion.

In contrast, alphabetic, chronological, and geographic filing systems are typically more straightforward. In an alphabetic system, files are arranged by names, making it easy to locate documents using a person's name without needing a cross-reference; chronological systems are organized by date and are generally intuitive for tracking timelines; geographic systems arrange files based on location, which also usually doesn't require a cross-reference due to the clear categorization by area. Therefore, numeric filing systems are uniquely reliant on cross-referencing for effective file management.