CodeDeploy deployment failures must be diagnosed using deployment-specific logs and related application logs. CodeDeploy writes detailed logs on the target EC2 instances under /opt/codedeploy-agent/deployment- root/ (for example in logs and deployment-logs subdirectories). These logs include information about lifecycle events (BeforeInstall, AfterInstall, ApplicationStart, etc.), script execution failures, permissions issues, and any exit codes returned by deployment hooks.
Option C correctly points to CodeDeploy agent logs on the EC2 instances as the primary source for root cause analysis. Additionally, application-level logs streamed to Amazon CloudWatch Logs help validate whether the application itself is working correctly after deployment. For complex, multi-tier applications, AWS X-Ray can trace requests end to end, helping determine if issues are caused by downstream dependencies instead of the deployment process.
Options A, B, and D focus on network flow, generic performance, or high-level checks, none of which provide sufficient, deployment-level detail for CodeDeploy. Trusted Advisor and AWS Health do not surface step-by-step deployment log data. Therefore, the combination of CodeDeploy logs on the instances, CloudWatch Logs, and (optionally) X-Ray is the correct troubleshooting approach.

https://aws.amazon.com/blogs/mt/monitor-changes-and-auto-enable-logging-in-aws-cloudtrail/

https://docs.aws.amazon.com/storagegateway/latest/APIReference/API_RefreshCache.html " It only updates the cached inventory to reflect changes in the inventory of the objects in the S3 bucket. This operation is only supported in the S3 File Gateway types."

The requirement is to automatically apply different baseline CloudFormation templates based on OU placement when new AWS accounts are created, while keeping operational overhead as low as possible.
Because the company is already using AWS Organizations and is planning a comprehensive account management strategy, the most AWS-native and efficient solution is AWS Control Tower with Customizations for AWS Control Tower (CfCT) .
CfCT is specifically designed to extend Control Tower's baseline by allowing administrators to deploy OU- scoped CloudFormation templates automatically. The solution uses a manifest file to map CloudFormation templates to specific OUs, ensuring that each new account receives the correct baseline configuration immediately after provisioning. Templates and configuration are stored in a version-controlled Git repository, providing auditability, change tracking, and rollback capabilities.
Option B adds unnecessary operational complexity by introducing a custom CodePipeline that must be manually triggered and maintained. This duplicates functionality that CfCT already provides natively. Options C and D rely on custom Lambda logic and EventBridge rules, which increase maintenance burden, reduce transparency, and lack built-in OU-aware governance features.
AWS documentation explicitly recommends Customizations for AWS Control Tower for OU-based, scalable, and automated baseline deployments. Therefore, Option A delivers the required functionality with the least operational overhead and aligns with AWS best practices for multi-account governance.

Step 1: Using Service Control Policies (SCPs) for EC2 SecurityTo limit the use of EC2 instance credentials to the specific EC2 instance they are assigned to, you can create a Service Control Policy (SCP) that verifies specific conditions, such as whether the EC2 instance's source VPC and private IP match expected values.
Action: Create an SCP that checks whether the values of the aws:EC2InstanceSourceVPC and aws:
SourceVpc condition keys are the same. Deny access if they are not.
Why: This ensures that credentials cannot be used outside the designated EC2 instance or VPC.
Step 2: Further Validation with Private IPsThe SCP should also verify that the EC2 instance's private IP matches the IP range specified for the VPC. If the instance's private IP does not match, access should be denied.
Action: In the same SCP, check whether the values of the aws:EC2InstanceSourcePrivateIP and aws:
VpcSourceIP condition keys are the same. Deny access if they are not.
Why: This ensures that the credentials are only used within the specific EC2 instance and its associated VPC.
Reference: AWS documentation on Service Control Policies (SCPs).
This corresponds to Option B: Create an SCP that checks whether the values of the aws:
EC2InstanceSourceVPC and aws:SourceVpc condition keys are the same. Deny access if the values are not the same. In the same SCP check, check whether the values of the aws:EC2InstanceSourcePrivateIP and aws:
VpcSourceIP condition keys are the same. Deny access if the values are not the same. Apply the SCP to the OU.