Jason, a cybersecurity analyst in the incident response team, begins investigating several complaints from employees...

Comprehensive and Detailed Explanation (ECIH-aligned):

This incident is a textbook example of whaling, a specialized form of phishing that targets senior executives or impersonates them to exploit authority and trust. According to the ECIH Email Security module, whaling attacks often focus on financial fraud, such as wire transfer requests or invoice manipulation, and are designed to bypass normal controls through urgency and executive impersonation.

Option A is correct because the attacker impersonated the CEO and targeted employees responsible for financial actions. The minor domain alteration and authoritative language are classic whaling indicators.

Option B refers to overwhelming inboxes with large volumes of mail. Option C involves automated credential testing. Option D targets mobile messaging platforms.

Jason’s response—header analysis, identity verification, firewall blocking, financial alerting, and organization-wide notification—aligns with ECIH best practices for handling executive impersonation attacks. Recognizing the attack type correctly is critical for appropriate escalation and mitigation, making Option A the correct answer.