A company has an organization in AWS Organizations with many OUs that contain many AWS...

The requirement specifies enforcing encryption before CloudFormation creates or updates resources. This is key because preventive enforcement must occur during the provisioning workflow, not after resources already exist. AWS provides CloudFormation Hooks specifically for this purpose. A Hook allows an organization to intercept a CloudFormation stack operation and validate resource configurations before provisioning occurs. This feature is recommended by AWS for pre-deployment governance such as enforcing encryption policies, tag compliance, or security restrictions.

By enabling trusted access between CloudFormation StackSets and AWS Organizations, the Hook can be deployed centrally from the delegated administrator account across all accounts in the specified OU. Any attempt to create or update EBS volumes or SQS queues through CloudFormation is validated first by the Hook. If encryption is not configured, the operation fails immediately.

Option C (SCP) blocks API calls globally, but SCPs cannot perform conditional logic based on resource properties passed by CloudFormation prior to creation. Option B (AWS Config) detects violations after resources already exist, which does not satisfy “before stack operation.” Option D (Lambda remediation) also occurs after the resource is created.

Thus, CloudFormation Hooks distributed via StackSets provide the only solution that enforces compliance before the provisioning lifecycle