A developer is creating a Ruby application and needs to automate the deployment, scaling, and management of an environment without requiring knowledge of the underlying infrastructure. Which service w

CodeDeploy automates application deployments to existing compute resources but does not manage scaling or infrastructure provisioning.

CloudFormation is an infrastructure-as-code service that requires explicit definition of underlying AWS resources, directly contradicting the no-infrastructure-knowledge requirement.

OpsWorks provides managed Chef and Puppet configuration management, which requires knowledge of server configuration and underlying infrastructure.

Elastic Beanstalk accepts application code (including Ruby) and fully manages the underlying EC2 instances, load balancers, Auto Scaling groups, and networking. Developers interact only with their code and configuration, satisfying the requirement of no infrastructure knowledge needed.