Which AWS service enables a company to define and provision its infrastructure using code (infrastructure as code)?

AWS CloudFormation is the correct answer because it allows you to define and provision AWS infrastructure resources in a declarative way using code (templates). This enables infrastructure as code, making it easier to manage, version, and replicate your cloud environment. AWS CodeDeploy is a service for automating code deployments to various compute services, not for provisioning infrastructure. AWS Elastic Beanstalk is an orchestration service for deploying and scaling web applications and services, abstracting the underlying infrastructure. Amazon API Gateway is a fully managed service that makes it easy for developers to create, publish, maintain, monitor, and secure APIs at any scale, not for infrastructure provisioning.