Which of the following functions as an instance-level (host) firewall to control inbound and outbound traffic?

Security groups act as an instance-level firewall, controlling inbound and outbound traffic for EC2 instances. They operate at the elastic network interface level, allowing you to specify rules for protocols, port ranges, and source/destination IP addresses or other security groups. This provides granular control over network access to your instances. Network Access Control Lists (NACLs) are stateless subnet-level firewalls, meaning they apply to all instances within a subnet and process rules for both inbound and outbound traffic separately. AWS Trusted Advisor is a service that provides recommendations for optimizing cost, performance, security, and fault tolerance, not a firewall. Virtual private gateways connect your VPC to your on-premises network, but do not function as a firewall.