An automated or manual file that stores information about data elements and characteristics is referred to as:

The correct answer is a data dictionary because it serves as a centralized repository that contains metadata about the data elements used within a system. A data dictionary details various characteristics of data, such as names, definitions, formats, allowable values, and relationships with other data. This resource is essential for developers, data analysts, and database administrators as it provides clarity and consistency in how data is defined and used throughout an organization.

In contrast, a data definition diagram primarily focuses on visual representations of data structures and is not primarily a repository of information like a data dictionary. An entity-relationship diagram also has a different purpose; it illustrates the relationships between various entities in a database, serving more as a design tool rather than a comprehensive source of metadata. The term relationship dictionary does not exist as a standard concept in data management and is therefore not relevant in this context. Thus, the data dictionary is the correct choice for representing a systematic storage of information about data elements and their characteristics.