Which of the following best describes the action of adding data into an existing database from another source, such as a spreadsheet or an external file?
The correct answer is 'Data import'. This action involves taking data from an external source file, like a CSV file or another type of data file, and adding it to an existing database. Data input generally refers to entering data manually using an input device or a user interface, while a database dump usually refers to exporting a database's contents for backup or transfer purposes, and data persistence refers to the characteristic of data that remains saved even after the application that created it has closed.