A company uses an organization in AWS Organizations to manage multiple AWS accounts in multiple...

The requirement is to automatically apply different baseline CloudFormation templates based on OU placement when new AWS accounts are created, while keeping operational overhead as low as possible. Because the company is already using AWS Organizations and is planning a comprehensive account management strategy, the most AWS-native and efficient solution is AWS Control Tower with Customizations for AWS Control Tower (CfCT) .

CfCT is specifically designed to extend Control Tower’s baseline by allowing administrators to deploy OU-scoped CloudFormation templates automatically. The solution uses a manifest file to map CloudFormation templates to specific OUs, ensuring that each new account receives the correct baseline configuration immediately after provisioning. Templates and configuration are stored in a version-controlled Git repository, providing auditability, change tracking, and rollback capabilities.

Option B adds unnecessary operational complexity by introducing a custom CodePipeline that must be manually triggered and maintained. This duplicates functionality that CfCT already provides natively. Options C and D rely on custom Lambda logic and EventBridge rules, which increase maintenance burden, reduce transparency, and lack built-in OU-aware governance features.

AWS documentation explicitly recommends Customizations for AWS Control Tower for OU-based, scalable, and automated baseline deployments. Therefore, Option A delivers the required functionality with the least operational overhead and aligns with AWS best practices for multi-account governance.