Currently, your deployment process consists of setting your load balancer to point to a maintenance page, turning off ea web application servers, deploying your code, turning the web application servers back on, and removing the maintenance page. Working with your development team, you've agreed that performing rolling deployments of your software would provide a better user experience and a more agile deployment process.
Which techniques could you use to provide a cost-effective rolling deployment process? (Choose two.)

A. Use the Amazon Elastic Cloud Compute (EC2) API to write a service to return a list of servers based on the tags for the application that needs deployment, and use Amazon Simple Queue Service to queue up all servers for a rolling deployment.
B. Re-deploy your application on AWS Elastic Beanstalk, and use Elastic Beanstalk rolling deployments.
C. Re-deploy your application on an AWS OpsWorks stack, and take advantage of OpsWorks rolling deployments.
D. Re-deploy your application using an AWS CloudFormation template, launch a new CloudFormation stack during each deployment, and then tear down the old stack.
E. Re-deploy your application using an AWS CloudFormation template with Auto Scaling group, and use update policies to provide rolling updates.
F. Using Amazon Simple Workflow Service, create a workflow application that talks to the Amazon EC2 API to deploy your new code in a rolling fashion.