Which security feature is available in the free mode of Microsoft Defender for Cloud?

The option referring to the secure score is the correct answer because it is a key feature of Microsoft Defender for Cloud that is accessible in its free tier. The secure score provides organizations with a comprehensive assessment of their security posture across Azure resources and helps identify security risks. It offers actionable recommendations to enhance security levels and prioritize improvements based on the organization's specific environment.

The secure score feature is valuable for organizations looking to establish best practices in security without incurring additional costs. It gives organizations visibility into how well they are adhering to security policies and provides a benchmark for improvement.

The other features mentioned, such as threat protection alerts, just-in-time VM access, and vulnerability scanning, typically require a higher tier of service that includes additional capabilities and protections that go beyond what is provided for free. Garnering insights from the secure score can empower organizations to make informed security decisions and implement necessary changes effectively.