Minimizing business downtime is critical when implementing a new system that supports an essential process like month-end closing.
Option A (Incorrect):Thebig bang approachinvolves replacing the old system with the new system all at once.
This method carries ahigh riskbecause if issues arise, they may causesignificant downtimeand disruption.
Option B (Correct):Aphased approachgradually implements the system in stages, allowing users toadaptand minimizing the risk of complete failure. This strategy is ideal for critical systems that cannot afford extended downtime.
Option C (Incorrect):Thecutover approachis a variation of big bang, where the old system is shut down, and the new system is activated. This method isriskyfor month-end processes because errors can causebusiness delays.
Option D (Incorrect):Theparallel approachruns both old and new systems simultaneously to verify accuracy, but it isresource-intensiveand may not be practical for a high-volume month-end process.
Reference:ISACA CISA Review Manual -Domain 3: Information Systems Acquisition, Development, and Implementation- Covers system implementation strategies, risk management, and best practices.

Explanation/Reference:
Explanation:
End user involvement is critical in the BIA phase. During this phase the current operations of the business needs to be understood and the impact on the business of various disasters must be evaluated. End users are the appropriate persons to provide relevant information for these tasks, inadequate end user involvement in this stage could result in an inadequate understanding of business priorities and the plan not meeting the requirements of the organization.

The use of a database administrator (DBA) user account is normally set up to log all changes made and is most appropriate for changes made outside of normal hours. The use of a log, which records the changes, allows changes to be reviewed. The use ofthe DBA user account without logging would permit uncontrolled changes to be made to databases once access to the account was obtained. The use of a normal user account with no restrictions would allow uncontrolled changes to any of the databases. Logging would only provide information on changes made, but would not limit changes to only those that were authorized. Hence, logging coupled with review form an appropriate set of compensating controls.