A CloudFormation template is used to deploy an application stack that includes a backend database. The development team would like to know if the existing database will be deleted or replaced before applying any template updates. What service feature will enable this?

Answer options:

A.CloudFormation Change Sets
B.CloudFormation Rolling Updates
C.CloudFormation StackSets
D.CloudFormation Registry

Answer: A
Option A is CORRECT because CloudFormation Change sets enable the preview of proposed changes to a stack to assess the impact on existing resources. This functionality allows the team to check if any existing databases will be deleted or replaced upon application of the updated CloudFormation template.
Option B is incorrect because CloudFormation rolling updates dictate how AWS CloudFormation handles deployment updates to AWS resources.
Option C is incorrect because CloudFormation StackSets is a CloudFormation feature that facilitates the deployment and management of CloudFormation templates across multiple AWS accounts.
Option D is incorrect because CloudFormation Registry provides a listing of available CloudFormation providers in an account that can be used in CloudFormation templates.
Reference:
https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-changesets.html