What is one key advantage of using CloudWatch Alarms?

Using CloudWatch Alarms provides a key advantage in enabling proactive monitoring of defined metrics. This functionality allows users to set thresholds for specific metrics—like CPU utilization, disk usage, or custom application metrics. When these metrics exceed or fall below the specified thresholds, CloudWatch Alarms can trigger notifications, initiate actions, or invoke other AWS services automatically. This proactive approach helps organizations quickly respond to performance issues, optimize resource usage, and maintain system reliability.

The other options do not accurately reflect the primary capabilities of CloudWatch Alarms. For instance, while CloudWatch can work with EC2 instances, it does not automate their creation; that involves services like Auto Scaling. Detailed logging of Lambda functions is more aligned with CloudWatch Logs rather than Alarms. Lastly, creating dashboards for visualizing S3 bucket data relates to CloudWatch's dashboard feature but is not directly tied to the functionality of alarms themselves. The strength of CloudWatch Alarms lies in their ability to monitor and alert based on critical system metrics, enhancing observability and operational efficiency.