The correct answer is Evaluate how well implemented security controls reduce known risks and weaknesses.

A security controls audit is primarily about assessing whether controls are designed and operating effectively to mitigate the risks they are intended to address. The auditor collects evidence, tests control operation, and determines if the controls actually reduce known risks and weaknesses in line with the organisation's risk treatment strategy. The result is an assurance opinion on control effectiveness rather than a simple checklist outcome.

Confirm that the system follows applicable laws and standards is focused on compliance. Compliance reviews and legal assessments check adherence to laws and standards and they may overlap with audits, but the primary goal of a controls audit is to test effectiveness of controls rather than to certify legal or regulatory conformity.

Find additional vulnerabilities and new threats within the system describes vulnerability assessments and penetration testing. Those activities actively search for unknown weaknesses and simulate attacks. Auditors may note vulnerabilities they observe, but discovery of new threats is not the main purpose of a controls audit.

Measure the enterprise level security posture and capability maturity is about high level posture assessments and maturity models. Those assessments evaluate overall capability and strategic maturity across the enterprise. A controls audit is usually narrower and concentrates on whether specific controls work as intended to reduce risk.

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