A VPC includes a public subnet where a NAT gateway is deployed and a private subnet with EC2 instances that use that NAT gateway to download updates. VPC flow logs for the NAT gateway's ENI are being sent to CloudWatch Logs. The SysOps administrator needs to determine the top five internet destinations that the private subnet instances contact for downloads. What is the most operationally efficient way to get this list?

CloudWatch Logs Insights is the most operationally efficient solution because it allows you to directly query the existing flow logs in CloudWatch Logs. You can write a query to parse the destination IP addresses from the NAT gateway's ENI logs and then aggregate and sort them to identify the top five. This avoids reconfiguring logging or introducing new services. CloudTrail Insights focuses on API activity, not network flow data. CloudFront access logs are for content delivery, not general internet traffic from EC2 instances. Reconfiguring flow logs to S3 and using Athena would work but is less efficient as it requires a configuration change and additional service setup compared to querying data already in CloudWatch Logs.