VPC Flow Logs is the correct answer because it captures information about the IP traffic going to and from network interfaces in your VPC.

Explanation of services:

• VPC Flow Logs: Specifically designed to capture network traffic metadata (source/destination IP, ports, protocol, etc.) for VPC network interfaces
• Amazon CloudWatch Logs: A general logging service that can store and monitor logs from various AWS services, but doesn't specifically capture network traffic
• AWS CloudTrail: Records API calls and management events for AWS accounts, focusing on governance and compliance
• AWS Identity and Access Management (IAM): Manages access to AWS services and resources, not network traffic logging

VPC Flow Logs help with troubleshooting connectivity issues, monitoring traffic patterns, and ensuring network security compliance.