Which level of CSA STAR needs the release of results related to security-properties monitoring based on the Cloud Trust Protocol (CTP)?

The correct answer is Level 3. At this level of the Cloud Security Alliance STAR (Security, Trust & Assurance Registry) program, cloud service providers are required to provide substantial assurance regarding their security management and privacy practices. Specifically, Level 3 emphasizes the necessity for independent third-party audits and requires the release of results concerning security-properties monitoring.

This means that providers must transparently share the outcomes of audits and any relevant security information derived from the Cloud Trust Protocol (CTP), which assesses various security properties. By making these results available, consumers of cloud services can assess and verify the trustworthiness and security controls of the service providers. This transparency is a key component of fostering trust and ensuring compliance with regulatory requirements, making Level 3 distinct in its requirements compared to the other levels.