A gaming company has multiple Amazon EC2 instances in a single Availability Zone for its multiplayer game that communicates with users on Layer 4. The chief technology officer (CTO) wants to make the architecture highly available and cost-effective.
What should a solutions architect do to meet these requirements? (Choose two.)?

A. Increase the number of EC2 instances. B. Decrease the number of EC2 instances. C. Configure a Network Load Balancer in front of the EC2 instances. D. Configure an Application Load Balancer in front of the EC2 instances. E. Configure an Auto Scaling group to add or remove instances in multiple Availability Zones automatically.