Automation in cybersecurity testing refers to the use of specialized software, scripts, and tools to execute security assessments with minimal to no human intervention. This practice is fundamental to modern security operations and development (DevSecOps) as it allows for continuous, scalable, and repeatable testing. Automated tools can perform tasks such as vulnerability scanning, static and dynamic application security testing (SAST/DAST), and configuration checking. This enhances the speed and efficiency of identifying potential security weaknesses across an organization's digital assets, enabling faster remediation and a more robust security posture.

A. Implementing security controls to prevent attacks: This describes security hardening and implementation, which are preventative actions, not the process of testing for existing vulnerabilities.

C. Performing physical tests on network infrastructure: This is a specific, often manual, subset of security testing and does not represent the broad concept of automation.

D. Conducting manual security tests: This is the direct antithesis of automation, relying on human expertise and effort to conduct security assessments.

1. National Institute of Standards and Technology (NIST). (2008). Special Publication 800-115, Technical Guide to Information Security Testing and Assessment. Section 4.2, "Security Testing and Examination Tools" (pp. 4-3 to 4-11), details various categories of automated tools, such as vulnerability scanners and web application scanners, used to systematically test for security flaws.

2. Cisco. (2023). What Is DevSecOps?. Cisco Learning & Certifications. In the "Key principles of DevSecOps" section, the document states, "Automating security testing and integration is a key principle," emphasizing the use of automated tools for SAST, DAST, and SCA within the CI/CD pipeline to find vulnerabilities automatically.

3. Pfleeger, C. P., Pfleeger, S. L., & Margulies, J. (2015). Security in Computing (5th ed.). Pearson Education. Chapter 8, "Program Security," discusses automated testing tools like static and dynamic program analyzers that are used to find security flaws in code without manual review, defining a core aspect of automated security testing. (This textbook is standard courseware in many university computer science programs).