The best recommendation to facilitate compliance with the regulation that requires organizations to report significant security incidents to the regulator within 24 hours of identification is to include the requirement in the incident management response plan. An incident management response plan is a document that defines the roles, responsibilities, procedures, and tools for managing security incidents effectively and efficiently.
Including the requirement in the incident management response plan can help ensure that security incidents are identified, classified, reported, and escalated in accordance with the regulation. The other options are not as effective as including the requirement in the incident management response plan, as they do not address all aspects of incident management or compliance. Establishing key performance indicators (KPIs) for timely identification of security incidents is a monitoring technique that can help measure and improve the performance of incident management processes, but it does not ensure compliance with the regulation.
Enhancing the alert functionality of the intrusion detection system (IDS) is a technical control that can help detect and notify security incidents faster, but it does not ensure compliance with the regulation. Engaging an external security incident response expert for incident handling is a contingency measure that can help augment the organization's internal capabilities and resources for managing security incidents, but it does not ensure compliance with the regulation. References: CISA Review Manual (Digital Version), Chapter 4, Section 4.2.2