Why would this template fail to deploy?
(Choose two.)
The template referenced an IAM user that is not available in eu-west-1.
The template referenced an Amazon Machine Image (AMI) that is not available in eu-west-1.
The template did not have the proper level of permissions to deploy the resources.
The template requested services that do not exist in eu-west-1.
CloudFormation templates can be used only to update existing services.
Explanations:
IAM users are global entities in AWS; they are not region-specific. Therefore, a referenced IAM user would be available in eu-west-1.
Amazon Machine Images (AMIs) are region-specific. If the template references an AMI that exists only in us-west-2, it will not be found in eu-west-1, causing the stack deployment to fail.
If the template had the necessary permissions in us-west-2, it would typically have similar permissions in eu-west-1, assuming the IAM roles and policies are configured correctly. Permissions issues are less likely to cause a regional deployment failure.
Some AWS services are not available in all regions. If the CloudFormation template includes resources or services that do not exist in eu-west-1, it will fail to deploy.
CloudFormation templates can be used to create new services as well as update existing ones. There are no restrictions on using templates based solely on existing services.
I deduce that the answer is:
The template referenced an Amazon Machine Image (AMI) that is not available in eu-west-1.