A web application runs on EC2 instances built from a custom AMI and is provisioned with CloudFormation in us-east-1. The company wants to deploy the same stack in us-west-1, but stack creation in us-west-1 fails with an error that the AMI ID does not exist. The developer must fix this with minimal operational effort. Which solution accomplishes that?

The correct solution is to copy the custom AMI from us-east-1 to us-west-1 and then update the CloudFormation template for us-west-1 to reference the new AMI ID. AMIs are region-specific, so an AMI created in us-east-1 cannot be directly used in us-west-1. Copying the AMI is a straightforward process that preserves the custom configuration. Updating the CloudFormation template ensures the new stack correctly references the available AMI in the target region. Modifying to an AWS-managed AMI would require re-configuring the application, which is not minimal effort. Rebuilding the AMI in us-west-1 is also more effort than simply copying it. Abandoning CloudFormation is not a viable solution as it loses the benefits of infrastructure as code.