The business application keeps writing files to an S3 bucket in an AWS production account. To meet the compliance requirements, the files in the S3 bucket should be replicated in another AWS region and another AWS account.
So even if there is an outage for a region or the AWS account is deleted, the files still have a backup and can be restored if required.
Which solution is the most appropriate one to achieve these requirements?

Answer options:

A.Configure a cross-region replication for the S3 bucket. The destination bucket belongs to a different AWS account. Both the source and destination buckets should enable versioning.
B.Use a CloudFormation template to create a Lambda function that copies the files from the source bucket and pastes them in another S3 bucket. Execute the Lambda function every 24 hours.
C.Configure the object upload event in the source S3 bucket and send the notifications to an SQS queue. Use a Lambda function to listen to the queue and synchronize files from the source bucket to the destination bucket.
D.Create a backup plan for the S3 bucket in AWS Backup. Define the schedule and retention rule in the plan which replicates files from the source bucket to the destination bucket.

Answer: A
Option A is CORRECT because the AWS S3 Replication feature enables automatic, asynchronous copying of objects across S3 buckets in the same or different AWS accounts.
Option B is incorrect because it is not suitable to run the Lambda function every 24 hours. With S3 Replication, objects can be replicated within 15 minutes. This would not be the most efficient and cost-effective solution.
Option C is incorrect because you need to maintain a Lambda function and an SQS queue to synchronize files.
Option A provides a more straightforward and efficient solution.
Option D is incorrect because AWS Backup does not support S3 replications. 
Reference:
https://docs.aws.amazon.com/AmazonS3/latest/dev/replication.html#crr-scenario