A company's compliance audit reveals that some Amazon Elastic Block Store (Amazon EBS) volumes that were created in an AWS account were not encrypted. A solutions architect must implement a solution…

Creating an Amazon EventBridge rule to detect unencrypted volumes and invoking a Lambda function to encrypt them is a reactive solution that requires custom code and maintenance, incurring more effort than simply enabling the default setting.

AWS Audit Manager helps automate auditing and compliance checks but does not actively implement encryption for newly created EBS volumes; it's a reporting and assessment tool.

An AWS Config rule can detect non-compliant (unencrypted) EBS volumes after creation, but to encrypt them would still require a remediation action, which adds more operational overhead than a default setting.

Turning on EBS encryption by default in all AWS Regions is the most straightforward and least effort solution. Once enabled, all new EBS volumes and snapshot copies created in that Region will be automatically encrypted, proactively meeting the compliance requirement without any additional reactive measures.