Option 1 correctly uses customer-managed KMS keys for both RDS and EBS, giving the company full control. Enabling automatic key rotation in KMS meets the rotation requirement. Using an encrypted AMI and enabling account-level default EBS encryption ensures all new volumes are encrypted by default. This is the most secure, manageable, and AWS-native approach that fully satisfies the control and rotation mandates.

NAT Gateways are managed services and do not have security groups; they rely on network ACLs and route tables. Flow logs show REJECT entries, which are typically the result of network ACL rules (stateless) blocking traffic, not a missing route (which would show as NODATA). When an instance initiates an outbound HTTPS (port 443) connection via a NAT Gateway, the return traffic comes back on a random ephemeral port. If the subnet’s network ACL inbound rules do not allow this ephemeral port range, the return packets will be rejected, causing the connection to fail.

AWS WAF is a web application firewall designed specifically to monitor HTTP/HTTPS requests and protect against common web exploits. It integrates seamlessly with ALB, is highly available and managed by AWS, scales automatically, and requires minimal operational overhead. Using managed rule sets provides immediate protection with best practices. AWS Network Firewall (Option A) is for broader network traffic, not optimized for deep HTTP/S inspection. Options C and D introduce significant complexity, operational overhead, and are not the most direct or managed solutions for the stated requirement.

The principle of least privilege is best enforced by centralizing permissions management. Removing individual user attachments and managing permissions solely through groups is a foundational best practice. It makes auditing simpler (check the group, not the user), prevents permission drift where users accumulate direct policies, and is more maintainable. While SSO (Option D) is excellent for human access, it doesn’t directly solve the existing IAM policy hygiene issue. Option B is a dangerous anti-pattern, and Option C, while using a useful tool, is more reactive and user-specific than the systemic fix of using groups.

Option A correctly addresses all requirements. A VPC Gateway Endpoint provides a private route from a VPC to S3 without internet traversal. The bucket policy enforcing this ensures compliance. S3 server access logging provides logs for bucket-level requests, and enabling CloudTrail data events for S3 (specifically for the bucket) captures API calls (like GetObject, PutObject) including identity and error codes, which is crucial for logging failed attempts. Option C’s Interface endpoint is for other AWS services, not S3 (which uses Gateway). Options B and D do not guarantee private network routing.

After credential revocation (containment), the next critical step in the incident response process is investigation/assessment. CloudTrail is the authoritative source for auditing API activity in an AWS account. Searching for the compromised user’s activity in the exposure window is essential to determine if the credentials were used, what actions were taken, and what resources might have been compromised. This informs subsequent recovery steps. Option B prioritizes convenience over security. Option C is insufficient as timestamps don’t show details of actions. Option D is a good general practice but is not the targeted, immediate forensic step required.

Amazon RDS Multi-AZ uses synchronous replication to a standby instance in another AZ. This means committed transactions are written to both instances before a commit is acknowledged, resulting in an RPO of nearly zero (no data loss). During a reboot with failover, RDS performs a DNS update to point to the new primary (standby). This DNS propagation is not instantaneous but typically completes within 1-2 minutes, which meets the stated 2-minute RTO. The other options misstate the replication type (it’s synchronous) or the failover mechanics.

The core threat is unauthorized use of the expensive Scan operation. The most effective mitigation is to enforce authorization and scope at the IAM layer. An IAM policy can use the `dynamodb:Scan` action with conditions (like `dynamodb:Select` or by restricting it to specific roles) to prevent its use by unauthorized principals. Combining this with application logic that limits result sets provides defense-in-depth. Option A protects against external traffic but not an internal compromised credential. Option B doesn’t address the operational cost of Scans. Option C (provisioned capacity) could impact legitimate traffic during a spike and is less precise than IAM control.

AWS Firewall Manager is a security management service that allows you to centrally configure and manage firewall rules and security policies across accounts and resources in an AWS Organization. Its S3 security policy type can enforce that S3 Block Public Access settings (a powerful account-level and bucket-level guardrail) are enabled for all accounts. This is a proactive, preventative control applied at scale. AWS Config (Option A) is detective, not preventative. SCPs (Option B) cannot directly manage resource-level settings like Block Public Access; they control IAM permissions. Option D is a custom, operational-heavy solution that is less robust than a managed service.

Option 1 correctly uses customer-managed KMS keys for both RDS and EBS, giving the company full control. Enabling automatic key rotation in KMS meets the rotation requirement. Using an encrypted AMI and enabling account-level default EBS encryption ensures all new volumes are encrypted by default. This is the most secure, manageable, and AWS-native approach that fully satisfies the control and rotation mandates.0