To identify AWS resources generating suspicious traffic with minimal cost and administrative overhead, the best approach is to use VPC flow logs and analyze them using Amazon CloudWatch Logs Insights. VPC flow logs capture information about the IP traffic going to and from network interfaces in your VPC. By publishing these logs to Amazon CloudWatch Logs, you can use CloudWatch Logs Insights to run queries and analyze the traffic patterns. This solution is cost-effective because it leverages existing AWS services without the need for additional infrastructure or complex configurations. Option C is the correct choice as it directly addresses the requirement to identify the source of suspicious traffic with minimal cost and administrative overhead. Option A involves additional infrastructure (EC2 instance) and complexity (Traffic Mirroring), which increases cost and administrative effort. Option B, while feasible, introduces a SIEM solution, which may not be necessary for this specific requirement and could increase costs. Option D involves a more complex setup with Kinesis and S3, which is not required for simply identifying the source of suspicious traffic and would likely incur higher costs.