Which of the following is NOT a form of email authentication?
Explanation: The correct answer is CPC. SPF (Sender Policy Framework), DKIM (DomainKeys Identified Mail), BIMI (Brand Indicators for Message Identification), and DMARC (Domain-based Message Authentication, Reporting, and Conformance) are all forms of email authentication aimed at verifying the authenticity of emails and ensuring they are not spoofed or tampered with. SPF allows domain owners to specify which IP addresses are allowed to send emails on behalf of their domain, DKIM adds a digital signature to emails to verify their authenticity, BIMI enhances brand visibility in email inboxes, and DMARC provides instructions on how email providers should handle messages that fail SPF and DKIM checks. On the other hand, CPC is not a recognized form of email authentication. It’s essential to implement robust email authentication protocols like SPF, DKIM, BIMI, and DMARC to enhance email deliverability, protect sender reputation, and combat phishing and spoofing attacks.