Which types of deployment can the developer use to meet this requirement?

Explanations:

The “All at once” deployment method updates all instances simultaneously, which does not meet the requirement of deploying changes to new instances only.

The “Immutable” deployment method creates new instances with the new version of the application and only swaps them in when they are fully ready, ensuring that the old instances remain unaffected during the deployment process.

The “Rolling” deployment method updates instances in batches, which means that some existing instances would still be running the old version during the deployment process. This does not align with the requirement to deploy changes to new instances only.

The “Blue/green” deployment method involves running two separate environments (blue and green). The new version is deployed to the inactive environment (green), and then traffic is switched to it, ensuring that the old version (blue) remains untouched until the new version is fully validated. This effectively meets the requirement.

The “Rolling with additional batch” deployment method updates instances in batches but with an added capacity to ensure availability. However, it still affects existing instances during the deployment, which does not fulfill the requirement of deploying changes only to new instances.