AES-256 is a symmetric encryption algorithm widely used to protect data at rest by converting plaintext into ciphertext that is unreadable without the proper key. It provides strong confidentiality and is a standard for encrypting stored data.
TLS 1.2 (A) secures data in transit, not at rest. Masking (C) obscures data but typically for display or limited use and is reversible. Salting (D) is used alongside hashing to protect passwords and data integrity but does not encrypt data.
Encryption with AES-256 is recognized as a best practice for securing stored data in the Security+ Cryptography and General Security Concepts domains#6:Chapter 7†CompTIA Security+ Study Guide#.

A tabletop exercise is a discussion-based simulation in which stakeholders review and talk through their roles, responsibilities, and actions in response to a hypothetical incident. This allows participants to evaluate and improve response plans without actual disruption.
Reference:
CompTIA Security+ SY0-701 Official Study Guide, Domain 5.6: "Tabletop exercises involve key stakeholders discussing roles, responsibilities, and actions in response to simulated incidents." Exam Objectives 5.6: "Given a scenario, implement security incident management processes."

SIEM stands for Security Information and Event Management. It is a security alerting and monitoring tool that collects system, application, and network logs from multiple sources in a centralized system. SIEM can analyze the collected data, correlate events, generate alerts, and provide reports and dashboards. SIEM can also integrate with other security tools and support compliance requirements. SIEM helps organizations to detect and respond to cyber threats, improve security posture, and reduce operational costs. References:
CompTIA Security+ Study Guide: Exam SY0-701, 9th Edition, Chapter 10: Monitoring and Auditing, page
393. CompTIA Security+ Practice Tests: Exam SY0-701, 3rd Edition, Chapter 10: Monitoring and Auditing, page 397.