A financial services company has a compliance requirement that all archived data must be preserved exclusively in a non-rewriteable and non-erasable format. What solution satisfies this requirement in the most cost-effective way?

Answer options:

A.Enable Amazon S3 Versioning.
B.Enable Amazon S3 Object Lock.
C.Implement Amazon S3 Bucket Policy with deny statements for object delete operations.
D.Implement Amazon S3 Glacier Vault Lock.

Answer: D
Option A is incorrect because Amazon S3 versioning does not protect object versions from being deleted.
Option B is incorrect because it is not the most cost-effective solution. The question specifically asks about archived data. Storing archived data in Amazon S3 Glacier is more cost-effective than Amazon S3.
Option C is incorrect because it does not satisfy the requirements. Amazon S3 bucket policies can be changed, thus removing protection on the objects.
Option D is CORRECT because Amazon S3 Glacier is the most cost-effective storage solution for archive data. Amazon S3 Glacier Vault Lock can be used to implement a “Write-Once-Read-Many” archive storage solution.
Reference
https://docs.aws.amazon.com/amazonglacier/latest/dev/vault-lock.html
https://aws.amazon.com/blogs/aws/glacier-vault-lock/