As an AWS system administrator, you need to maintain CloudFormation templates used to deploy an application in multiple AWS Regions. At the moment, each AWS region has its own CloudFormation template as the AMI ID is different per region. You want to parameterize the AMI ID so that the same CloudFormation template can be reused for different AWS Regions. Which of the following options is the most suitable?

Answer options:

A.Use the “Parameters” section to define the AMI ID per region and return the correct AMI ID through the “Fn::FindInParameter” intrinsic function.
B.Use “Conditions” to include different AMI IDs per region and return the correct AMI ID through the “Fn::If” intrinsic function.
C.Use “Metadata” to define different AMI IDs per region and return the correct AMI ID through the “Fn::FindInMetadata” intrinsic function.
D.Use “Mappings” to include different AMI IDs per region and return the correct AMI ID through the “Fn::FindInMap” intrinsic function.

Correct Answer: D
Option A is incorrect because there is no “Fn::FindInParameter” intrinsic function. It is not how parameters are used in CloudFormation. To reference a parameter, you need to use the “Ref” intrinsic function.
Option B is incorrect because “Conditions” are used to define different circumstances. The “Conditions” section is not suitable to define AMI IDs.
Option C is incorrect because the optional “Metadata” section provides details about the template such as descriptions. It cannot define AMI IDs.
Option D is CORRECT because the “Mappings” section is suitable to create a mapping with key/value pairs. In this case, the key is the AWS region, and the value is the AMI ID. The values in the map can be retrieved through the “Fn::FindInMap” function.
Reference:
https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/mappings-section-structure.html