The first course of action for an organization that has received notification that it is a potential victim of a cybercrime that may have compromised sensitive customer data is to invoke the incident response plan. An incident response plan is a set of procedures and guidelines that defines the roles and responsibilities of the incident response team, the communication and escalation channels, the incident identification and classification criteria, the incident containment and eradication strategies, the incident recovery and restoration activities, and the incident documentation and reporting requirements. Invoking the incident response plan as soon as possible is crucial to minimize the damage and disruption caused by the cybercrime, to preserve the evidence and facilitate the investigation, and to comply with the legal and regulatory obligations. The other options are not the first course of action, although they may be subsequent or concurrent steps in the incident response process. Determining the business impact is a part of the incident assessment and prioritization phase, which helps to evaluate the severity and scope of the incident and to allocate the appropriate resources and actions. Conducting a forensic investigation is a part of the incident analysis and evidence collection phase, which helps to identify the source and cause of the incident and to support the legal and disciplinary actions.
Invoking the business continuity plan (BCP) is a part of the incident recovery and restoration phase, which helps to resume the normal operations and services and to mitigate the adverse effects of the incident.
References = The National Cyber Incident Response Plan (NCIRP), Cyber Incident Response Plan | Cyber.gov.au, [Cyber Incident Response: A Framework for Preparation and Success], [Cyber Incident Response Plan: How to Create One for Your Business]