How should the administrator ensure that the AWS Cloud Formation template is working in every region?

A SysOps administrator Is troubleshooting an AWS Cloud Formation template whereby multiple Amazon EC2 instances are being created.

The template is working In us-east-1. but it is failing In us-west-2 with the error code:

How should the administrator ensure that the AWS Cloud Formation template is working in every region?
A . Copy the source region’s Amazon Machine Image (AMI) to the destination region and assign it the same ID.
B . Edit the AWS CloudFormatton template to specify the region code as part of the fully qualified AMI ID.
C . Edit the AWS CloudFormatton template to offer a drop-down list of all AMIs to the user by using the aws :: EC2:: ami :: imageiD control.
D . Modify the AWS CloudFormation template by including the AMI IDs in the "Mappings" section. Refer to the proper mapping within the template for the proper AMI ID.

View Answer

Answer: A