The correct answer is B — Regularly backing up the data stored in the POS system and having a disaster recovery plan can help ensure that the system is available in the event of a security incident or system failure.
As explained in WGU Cybersecurity Architecture and Engineering (KFO1 / D488), backing up critical systems and establishing a disaster recovery plan ensures business continuity and system availability even after incidents like hardware failures, cyberattacks, or data corruption.
While intrusion detection (A), access control (C), and patch management (D) contribute to overall security, backups and disaster recovery specifically ensure availability.
Reference Extract from Study Guide:
"Data backups and disaster recovery planning are essential controls to ensure system availability during and after a security incident or technical failure."
— WGU Cybersecurity Architecture and Engineering (KFO1 / D488), Business Continuity and Disaster Recovery
=============================================
