You are in charge of designing a number of Cloudformation templates for your organization. You need to ensure that no one can accidentally update the production based resources on the stack during a stack update. How can this be achieved in the most efficient way?

Answer options:

A.Create tags for the resources and then create IAM policies to protect the resources.
B.Use a Stack based policy to protect the production based resources.
C.Use S3 bucket policies to protect the resources.
D.Use MFA to protect the resources

Answer – B
The AWS Documentation mentions
When you create a stack, all update actions are allowed on all resources. By default, anyone with stack update permissions can update all of the resources in the stack. During an update, some resources might require an interruption or be completely replaced, resulting in new physical IDs or completely new storage. You can prevent stack resources from being unintentionally updated or deleted during a stack update by using a stack policy. A stack policy is a JSON document that defines the update actions that can be performed on designated resources.
For more information on protecting stack resources , please visit the below url
http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/protect-stack-resources.html