Correct answer - "CloudTrail" : CloudTrail provides event history of your AWS account activity,
including actions taken through the AWS Management Console, AWS SDKs, command line tools, and
other AWS services. This event history simplifies security analysis, resource change tracking,
and troubleshooting.
"SNS" - SNS can be used to send notifications whenever there are changes to the execution state
of your pipelines, or in the stages or actions in your pipelines
"SQS" - When you publish approval notifications to Amazon SNS topics, you can choose from formats
such as email or SMS recipients, SQS queues in regards to CodePipeline
"CloudWatch" - You can create a CloudWatch Events notification rule with AWS CodePipeline as the
event source to integrate them together
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