The best way to test the operational effectiveness of a data backup procedure is to perform a complete restoration of every file to a clean system and verify that there has not been any data corruption or loss. This will ensure that the backup procedure can successfully recover the data in the event of a disaster or incident.
The other options are not sufficient to test the operational effectiveness of a data backup procedure, as they do not involve actually restoring the data and verifying its integrity and usability. References = How to review and test backup procedures to ensure data restoration; HOW TO TEST DATA BACKUPS: A BRIEF GUIDE; How to Test a Database Backup

The greatest challenge to assigning of the associated risk entries when an organization has used generic risk scenarios to populate its risk register is that the risk scenarios are not applicable. Generic risk scenarios are risk scenarios that are based on common or typical situations that may affect many organizations or industries.
They are useful for providing a general overview or reference of the potential risks, but they may not be relevant, specific, or realistic for a particular organization or context. Therefore, using generic risk scenarios may result in inaccurate, incomplete, or misleading risk entries that do not reflect the actual risk profile or appetite of the organization. The other options are not as challenging as the risk scenarios being not applicable, as they are related to the quantity, quality, or aggregation of the risk scenarios, not the suitability or validity of the risk scenarios. References = Risk and Information Systems Control Study Manual, Chapter 1: IT Risk Identification, Section 1.3: IT Risk Scenarios, page 23.

Section: Volume D