SPF (Sender Policy Framework) DNS records specify which mail servers are authorized to send email on behalf of a domain. When new email servers are added but SPF records are not updated, recipient mail systems cannot verify the legitimacy of the new servers. As a result, those messages are flagged as spam or rejected altogether.
CompTIA Security+ SY0-701 highlights SPF as an essential email authentication mechanism used to reduce spoofing, phishing, and spam classification errors. Updating the SPF record to include the new servers ensures email reputation is maintained and messages are delivered properly.
CNAME (A) maps hostnames but does not affect outbound email legitimacy. SMTP (B) is the mail protocol, not the authentication method. DLP (C) governs sensitive data handling, not spam classification.
Thus, SPF is the correct answer.

The chmod command is used to change file permissions on Unix and Linux systems. If the /etc/shadow file has permissions beyond the baseline recommendation, the systems administrator should use chmod to modify the file's permissions, ensuring it adheres to the security baseline and limits access to authorized users only.
References = CompTIA Security+ SY0-701 study materials, focusing on system hardening and file permissions management.

Updating wire transfer processes to include verification steps (such as requiring dual approval or verifying account changes via a secondary communication method) canprevent fraudulenttransactions. Attackers often use business email compromise (BEC) or pretexting to trick employees into transferring funds to fraudulent accounts.
Standardizing security incident reportingis useful for tracking security events but does not prevent fraud in real time.
Executing regular phishing campaignsimproves awareness but does not enforce a verification process for financial transactions.
Implementing insider threat detectionfocuses on internal risks but does not specifically prevent external fraud.
Amore secure wire transfer processwith additional verification steps is the most effective measure against fraudulent transactions.