Which combination of steps should the security engineer take to meet these requirements?

Explanations:

While configuring RDS event notifications can alert on changes, it does not provide a direct compliance check or ensure near-real-time notification for noncompliance with public accessibility. This option alone does not fulfill the requirement of monitoring for compliance.

The rds-instance-public-access-check AWS Config managed rule actively monitors RDS instances for compliance regarding their public accessibility setting, which directly aligns with the requirement to ensure none of the resources are publicly accessible.

Configuring an Amazon EventBridge rule to target an SNS topic allows for immediate notifications to the security engineer when a change in compliance is detected, thus providing near-real-time alerts as required.

This approach, involving SQS and SNS, introduces unnecessary complexity. While it can send notifications, it does not directly monitor compliance or provide real-time alerts based on the RDS public access setting.

This option directly connects the compliance change detected by the AWS Config rule to a notification system, ensuring that any noncompliance regarding public accessibility is flagged in near-real-time, which meets the requirement.

While this option involves a Lambda function, it relies on notifications from the function to AWS Config, which is not necessary since the AWS Config rule can directly trigger notifications. This adds unnecessary steps and complexity to the monitoring process.