Using Intrinsic Functions in AWS CloudFormation Templates

Answer - B.

This is clearly given in the AWS documentation.

Intrinsic Function Reference.

AWS CloudFormation provides several built-in functions that help you manage your stacks.

Use intrinsic functions in your templates to assign values to properties that are not available until runtime.

Note:

You can use intrinsic functions only in specific parts of a template.

Currently, you can use intrinsic functions in resource properties, outputs, metadata attributes, and update policy attributes.

You can also use intrinsic functions to create stack resources conditionally.

For more information on intrinsic function, please refer to the below link.

https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/intrinsic-function-reference.html

When creating an AWS CloudFormation template, you can use intrinsic functions to assign values to properties that are not available until runtime. Intrinsic functions are used to perform dynamic evaluations and transformations in the template. The available intrinsic functions in CloudFormation include Fn::Base64, Fn::FindInMap, Fn::GetAtt, Fn::GetAZs, Fn::ImportValue, Fn::Join, Fn::Select, Fn::Split, Fn::Sub, and Ref.

Regarding the availability of intrinsic functions in different parts of a CloudFormation template, the correct answer is B. You can use intrinsic functions only in specific parts of a template. Currently, you can use intrinsic functions in resource properties, outputs, metadata attributes, and update policy attributes.

Resource properties: Intrinsic functions can be used to set property values for resources. For example, Fn::GetAtt can be used to retrieve the value of an attribute from another resource, and Ref can be used to reference the value of a resource.

Outputs: Intrinsic functions can also be used to define the outputs of a CloudFormation stack. For example, Fn::Join can be used to concatenate values and output them as a string.

Metadata attributes: Intrinsic functions can be used in the metadata section of a resource. For example, Fn::Base64 can be used to encode data in Base64 format.

Update policy attributes: Intrinsic functions can be used in the update policy section of a resource. For example, Fn::Join can be used to specify multiple notification targets for stack updates.

Note that intrinsic functions cannot be used in the AWSTemplateFormatVersion and Description sections of the template. The AWSTemplateFormatVersion section specifies the format version of the CloudFormation template, and the Description section provides a description of the template.