Correct answer - "rolling" : Deploys the new version in batches. Each batch is taken out of
service during the deployment phase, reducing your environment's capacity by the number of
instances in a batch. The cost remains the same as the number of EC2 instances does not increase
Incorrect:
"immutable" - Deploys the new version to a fresh group of instances
"all at once" - Deploys the new version to all instances simultaneously. All instances in your
environment are out of service for a short time while the deployment occurs.
"rolling with additional batches" - Deploys the new version in batches, but first launch a new
batch of instances to ensure full capacity during the deployment process. This increases cost as
you're creating extra instances during the deployment.
"blue/green" - Incurs charges because deploys a new version to a separate environment, and then
swaps CNAMEs of the two environments to redirect traffic to the new version instantly