What is server immutability?

instance usage is considered temporary or ephemeral in nature for the period of deployment until the current release is active. During the new release, a new set of EC2 instances are rolled out by terminating older instances. This type of upgrade technique is more common in an immutable infrastructure. https://d0.awsstatic.com/whitepapers/overview-of-deployment-options-on-aws.pdf

A.
Not updating a server after creation.

B.
The ability to change server counts.

C.
Updating a server after creation.

D.
The inability to change server counts.

Explanation:
Explanation/Reference:
… disposable upgrades offer a simpler way to know if your application has unknown dependencies. The underlying EC2