A tabletop exercise is a simulated scenario that tests the organization's incident response plan and procedures.
It involves key stakeholders and decision-makers who discuss their roles and actions in response to a hypothetical incident. It can help identify gaps, weaknesses, and improvement areas in the incident response process. It can also enhance communication, coordination, and collaboration among the participants. References: CompTIA Security+ Study Guide: Exam SY0-701, 9th Edition, page 525 1

When new email servers are deployed, organizations must update their SPF (Sender Policy Framework) records to list the new servers as authorized senders. If the SPF DNS record does not include the new IP addresses, recipient mail systems cannot verify the legitimacy of the messages, causing them to be flagged as spam or rejected.
Security+ SY0-701 identifies SPF as a key email authentication mechanism responsible for preventing:
Email spoofing
Unauthorized sender impersonation
False spam detection
Domain reputation issues
CNAME (A) maps domain aliases but does not authenticate email. SMTP (B) is the mail protocol and does not influence spam classification. DLP (C) prevents data leakage, not spam filtering.
Updating the SPF record resolves legitimacy issues by informing receiving mail servers that the new email servers are trusted.
Thus, the correct answer is D: SPF.

Side loading is the process of installing software outside of a manufacturer's approved software repository.
This can expose the device to potential vulnerabilities, such as malware, spyware, or unauthorized access.
Side loading can also bypass security controls and policies that are enforced by the manufacturer or the organization. Side loading is often done by users who want to access applications or features that are not available or allowed on their devices. References = Sideloading - CompTIA Security + Video Training | Interface Technical Training, Security+ (Plus) Certification | CompTIA IT Certifications, Load Balancers - CompTIA Security+ SY0-501 - 2.1, CompTIA Security+ SY0-601 Certification Study Guide.

Air-gapping is the most effective way to protect an application server running unsupported software from network threats. By physically isolating the server from any network connection (no wired or wireless communication), it is protected from external cyber threats. While other options like port security or a screened subnet can provide some level of protection, an air gap offers the highest level of security by preventing any network-based attacks entirely.
References =
* CompTIA Security+ SY0-701 Course Content: Domain 03 Security Architecture.
* CompTIA Security+ SY0-601 Study Guide: Chapter on Secure System Design.

A Service Level Agreement (SLA) is a formal document between a service provider and a client that defines the expected level of service, including what resources will be provided and the agreed-upon time frames. It typically includes metrics to evaluate performance, uptime guarantees, and response times.
* MOU (Memorandum of Understanding) and MOA (Memorandum of Agreement) are less formal and may not specify the exact level of service.
* BPA (Business Partners Agreement) focuses more on the long-term relationship between partners.