A web application runs on EC2 instances behind an Application Load Balancer and is reachable via a public URL. A SysOps administrator needs a monitoring solution that mimics customer interactions (following the same paths and actions) and will alert when fewer than 95% of checks succeed. Which solution satisfies this requirement?

CloudWatch Synthetics canaries are designed for actively monitoring web applications by simulating user interactions, making them ideal for mimicking customer paths and actions. The SuccessPercent metric directly tracks the success rate of these synthetic transactions, allowing for an alarm to be set when it falls below 95%. Route 53 health checks primarily monitor endpoint availability, not complex user journeys. While Lambda functions can be used for custom checks, CloudWatch Synthetics provides a more integrated and purpose-built solution for synthetic monitoring with built-in metrics and easier management of complex scripts compared to writing and maintaining multiple custom Lambda functions for each path.