A company uses a single AWS account (no Organizations) and has a CodePipeline that must test CloudFormation templates in the primary Region and a disaster-recovery (DR) Region. What solution provides the most operational efficiency?

CloudFormation StackSets are designed for deploying CloudFormation stacks across multiple AWS accounts and Regions from a single CloudFormation template. This directly addresses the requirement of deploying and testing templates in both a primary and a DR Region, offering the highest operational efficiency by centralizing the deployment process. Incorrect options: Adding a CodeDeploy action for each Region would be inefficient. CodeDeploy is primarily for deploying application revisions to instances or serverless functions, not for managing CloudFormation stack deployments across multiple Regions. Having CodePipeline invoke CodeBuild for each Region to deploy and test would work but is less efficient than StackSets. It would require managing separate CodeBuild projects or complex buildspec logic to handle cross-Region deployments, adding complexity. Snyk is a security tool for finding vulnerabilities in code and dependencies, not for deploying or testing CloudFormation templates. It is irrelevant to the deployment mechanism.