What is the function of AWS CodeDeploy?

AWS CodeDeploy is designed specifically to automate the deployment of applications to various compute services, including Amazon EC2 instances, on-premises servers, and AWS Lambda. This service facilitates a smooth and efficient deployment process by managing the complexity of deploying applications, allowing developers to focus on building rather than deploying.

With AWS CodeDeploy, you can deploy application code to a fleet of instances in a way that minimizes potential downtimes and ensures that updates are rolled out without affecting the availability of your application. It supports both blue/green and rolling deployment strategies which enhance the flexibility of deployment approaches.

Other options do not align with the core purpose of AWS CodeDeploy. For example, creating virtual servers is predominantly the function of Amazon EC2, while monitoring application performance is typically handled by services like Amazon CloudWatch. Backup solutions for data are more aligned with services such as AWS Backup or Amazon S3 for data storage. Thus, the primary function of automating the deployment of applications distinguishes AWS CodeDeploy as the correct answer.