A company plans to send promotional notifications using Amazon SNS FIFO topics. They need to measure the publish rate and the latency of these topics. Which approach gives the required telemetry with the least operational overhead?

AWS X-Ray, with active tracing enabled for Amazon SNS, is the most suitable option for measuring publish rate and latency. X-Ray provides detailed traces of requests as they travel through your application, including the time spent in SNS, directly addressing the need for latency and rate metrics. Using the Amazon CloudWatch NumberOfNotificationsFailed metric would only show failures, not overall publish rate or latency. AWS CloudTrail records API calls but doesn't inherently provide performance metrics like latency or throughput without additional processing. Amazon GuardDuty is a threat detection service and is not designed for application performance monitoring.