Which approach is most suitable for identifying a system's vulnerabilities before an attack occurs?

Penetration testing is a proactive cybersecurity strategy specifically designed to identify and exploit vulnerabilities in a system before an attacker can. By simulating real-world attack scenarios, penetration testing allows organizations to assess their security posture comprehensively. This process involves ethical hackers or security professionals who attempt to break into the system, thereby uncovering security weaknesses such as misconfigurations, unpatched software, and other vulnerabilities that could be leveraged by malicious actors.

Conducting penetration tests helps organizations understand the potential impact of an attack and prioritize remediation efforts based on the severity and exploitability of the discovered vulnerabilities. This makes penetration testing a vital part of an organization's risk management strategy, as it not only identifies weaknesses but also provides insights and recommendations for strengthening defenses.

In contrast, other options such as an incident response plan, threat hunting, and compliance review have different focuses. An incident response plan is a reactive measure that outlines procedures for responding to cybersecurity incidents after they occur. Threat hunting involves actively searching for signs of threats within a network but does not systematically test for vulnerabilities like penetration testing does. Compliance reviews check adherence to regulations or standards but may not encompass comprehensive vulnerability assessments. Thus, penetration testing is chosen as the most appropriate approach for identifying vulnerabilities proactively.