The AWS Cloud Development Kit (AWS CDK) is the correct answer because it allows developers to define cloud infrastructure using familiar programming languages like TypeScript, Python, Java, and C#. Unlike AWS CloudFormation which uses JSON/YAML templates, AWS CDK enables infrastructure-as-code using actual programming languages, providing benefits like code reuse, abstraction, and better development workflows. AWS CodePipeline is a continuous delivery service, and AWS Systems Manager is for operational data and automation tasks.