Limiting access to a software system through passwords supports the security objective of access control. Access control ensures that only authorized users can enter the system or perform specific actions based on identity, role, privilege, or permission. Passwords are one authentication mechanism used to verify identity before access is granted. An audit trail records user actions and system events, but passwords do not by themselves supply complete audit records. Preserving data integrity means protecting data from unauthorized or improper modification, which access control may support indirectly. Backup and recovery protect availability and restoration after failure or loss. Since the question specifically describes restricting system entry through passwords, the security objective being met is maintaining access control.

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