You Are Building Out a Layer in a Software Stack

Multiple Choice

You are building out a layer in a software stack on AWS that needs to be able to scale out to react to increased demand as fast as possible. You are running the code on EC2 instances in an Auto Scaling Group behind an ELB. Which application code deployment method should you use?

A) SSH into new instances that come online, and deploy new code onto the system by pulling it from an S3 bucket, which is populated by code that you refresh from source control on new pushes.
B) Bake an AMI when deploying new versions of code, and use that AMI for the Auto Scaling Launch Configuration.
C) Create a Dockerfile when preparing to deploy a new version to production and publish it to S3. Use UserData in the Auto Scaling Launch configuration to pull down the Dockerfile from S3 and run it when new instances launch.
D) Create a new Auto Scaling Launch Configuration with UserData scripts configured to pull the latest code at all times.