A company plans to publish a new application and must conform with security standards. Which of the following types of testing are MOST important for the systems administrator to run to assure the sec

Regression testing verifies that new code changes have not broken existing functionality, which is a quality assurance concern rather than a security or compliance concern.

Vulnerability testing systematically scans an application for known security flaws such as misconfigurations, outdated libraries, and CVEs, which is essential for meeting compliance standards before release.

Usability testing evaluates the end-user experience and interface design, providing no security or compliance validation.

Functional testing confirms that application features behave according to specifications but does not assess the security posture or compliance of the application.

Penetration testing simulates real-world attacker techniques to actively exploit identified or unknown weaknesses, providing proof-of-exploitability evidence that is required by many security standards such as PCI-DSS and SOC 2.

Load testing measures application behavior and stability under high traffic conditions, addressing performance rather than security vulnerabilities or compliance requirements.