Given the policy definitions available in the subscription, which definitions can be assigned as a Defender for Cloud security policy?

In Azure Defender for Cloud, security policies are implemented using Azure Policy initiatives. An initiative (policy set) is a collection of policy definitions that are grouped together to achieve a single, larger goal. Defender for Cloud leverages these initiatives to define the security configurations and compliance standards for your Azure resources. Individual policy definitions (like Policy1 and Policy2) cannot be directly assigned as a Defender for Cloud security policy; they must be part of an initiative. Therefore, only Initiative1 and Initiative2, which are policy initiatives, can be assigned as Defender for Cloud security policies.